U.S. patent number 11,063,265 [Application Number 16/536,112] was granted by the patent office on 2021-07-13 for diatomaceous energy storage devices.
This patent grant is currently assigned to Printed Energy Pty Ltd. The grantee listed for this patent is Printed Energy Pty Ltd. Invention is credited to John G. Gustafson, Sri Harsha Kolli, Vera N. Lockett, William J. Ray, Yasser Salah.
United States Patent |
11,063,265 |
Lockett , et al. |
July 13, 2021 |
Diatomaceous energy storage devices
Abstract
The disclosed technology generally relates to energy storage
devices, and more particularly to energy storage devices comprising
frustules. According to an aspect, a supercapacitor comprises a
pair of electrodes and an electrolyte, wherein at least one of the
electrodes comprises a plurality of frustules having formed thereon
a surface active material. The surface active material can include
nanostructures. The surface active material can include one or more
of a zinc oxide, a manganese oxide and a carbon nanotube.
Inventors: |
Lockett; Vera N. (Phoenix,
AZ), Salah; Yasser (Tempe, AZ), Gustafson; John G.
(Chandler, AZ), Ray; William J. (Fountain Hills, AZ),
Kolli; Sri Harsha (Tempe, AZ) |
Applicant: |
Name |
City |
State |
Country |
Type |
Printed Energy Pty Ltd |
Brisbane |
N/A |
AU |
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Assignee: |
Printed Energy Pty Ltd
(Brisbane, AU)
|
Family
ID: |
1000005676863 |
Appl.
No.: |
16/536,112 |
Filed: |
August 8, 2019 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20190363370 A1 |
Nov 28, 2019 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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15926896 |
Mar 20, 2018 |
10396365 |
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15808757 |
Oct 23, 2018 |
10109864 |
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15406407 |
Nov 21, 2017 |
9825305 |
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14745709 |
Jan 17, 2017 |
9548511 |
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14161658 |
Jul 14, 2015 |
9083010 |
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13944211 |
Sep 15, 2015 |
9136065 |
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61862469 |
Aug 5, 2013 |
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61750757 |
Jan 9, 2013 |
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61673149 |
Jul 18, 2012 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01G
11/46 (20130101); H01G 11/52 (20130101); H01G
11/26 (20130101); H01M 4/9016 (20130101); H01M
4/483 (20130101); H01G 11/24 (20130101); H01G
11/36 (20130101); H01M 4/502 (20130101); H01G
11/10 (20130101); H01M 8/16 (20130101); H01M
4/625 (20130101); H01M 2300/0045 (20130101); H01M
10/05 (20130101); H01G 11/02 (20130101); H01M
6/40 (20130101); Y02E 60/50 (20130101); Y02E
60/13 (20130101) |
Current International
Class: |
H01G
11/00 (20130101); H01M 4/62 (20060101); H01M
4/90 (20060101); H01G 11/46 (20130101); H01G
11/36 (20130101); H01G 11/24 (20130101); H01G
11/52 (20130101); H01G 11/10 (20130101); H01G
11/26 (20130101); H01M 4/48 (20100101); H01M
4/50 (20100101); H01M 8/16 (20060101); H01M
10/05 (20100101); H01M 6/40 (20060101); H01G
11/02 (20130101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
1391705 |
|
Jan 2003 |
|
CN |
|
1427494 |
|
Jul 2003 |
|
CN |
|
1973397 |
|
May 2007 |
|
CN |
|
101185888 |
|
May 2008 |
|
CN |
|
101310899 |
|
Nov 2008 |
|
CN |
|
101960546 |
|
Jan 2011 |
|
CN |
|
102007070 |
|
Apr 2011 |
|
CN |
|
102049527 |
|
May 2011 |
|
CN |
|
102070151 |
|
May 2011 |
|
CN |
|
102198946 |
|
Sep 2011 |
|
CN |
|
102208611 |
|
Oct 2011 |
|
CN |
|
102208640 |
|
Oct 2011 |
|
CN |
|
102290245 |
|
Dec 2011 |
|
CN |
|
102306767 |
|
Jan 2012 |
|
CN |
|
102558979 |
|
Jul 2012 |
|
CN |
|
102784926 |
|
Nov 2012 |
|
CN |
|
103178283 |
|
Jun 2013 |
|
CN |
|
103182293 |
|
Jul 2013 |
|
CN |
|
103227321 |
|
Jul 2013 |
|
CN |
|
103864395 |
|
Jun 2014 |
|
CN |
|
102941060 |
|
Oct 2014 |
|
CN |
|
104584160 |
|
Apr 2015 |
|
CN |
|
10157272 |
|
Jun 2003 |
|
DE |
|
0 618 629 |
|
Oct 1994 |
|
EP |
|
0 875 950 |
|
Nov 1998 |
|
EP |
|
1 630 891 |
|
Dec 2010 |
|
EP |
|
59139574 |
|
Aug 1984 |
|
JP |
|
63-248071 |
|
Oct 1988 |
|
JP |
|
06-260208 |
|
Sep 1994 |
|
JP |
|
06251759 |
|
Sep 1994 |
|
JP |
|
07-304984 |
|
Nov 1995 |
|
JP |
|
2000-003713 |
|
Jan 2000 |
|
JP |
|
3121137 |
|
Dec 2000 |
|
JP |
|
2001-176554 |
|
Jun 2001 |
|
JP |
|
2003-077445 |
|
Mar 2003 |
|
JP |
|
2006-108047 |
|
Apr 2006 |
|
JP |
|
2010-155761 |
|
Jul 2010 |
|
JP |
|
2012-033366 |
|
Feb 2012 |
|
JP |
|
2014-154260 |
|
Aug 2014 |
|
JP |
|
2015-191848 |
|
Nov 2015 |
|
JP |
|
10-2012-0061932 |
|
Jun 2012 |
|
KR |
|
10-2012-0125385 |
|
Nov 2012 |
|
KR |
|
200740011 |
|
Oct 2007 |
|
TW |
|
201016715 |
|
May 2010 |
|
TW |
|
I608647 |
|
Dec 2017 |
|
TW |
|
WO 2000/055930 |
|
Sep 2000 |
|
WO |
|
WO 2007/116649 |
|
Oct 2007 |
|
WO |
|
WO 2012/037171 |
|
Mar 2012 |
|
WO |
|
WO 2014/014758 |
|
Jan 2014 |
|
WO |
|
WO 2014/015074 |
|
Jan 2014 |
|
WO |
|
WO 2014/106088 |
|
Mar 2014 |
|
WO |
|
WO 2014/059127 |
|
Apr 2014 |
|
WO |
|
WO 2015/009867 |
|
Jan 2015 |
|
WO |
|
WO 2016/209655 |
|
Dec 2016 |
|
WO |
|
WO 2019/182874 |
|
Sep 2019 |
|
WO |
|
Other References
Augustyn et al., "Pseudocapacitive oxide materials for high-rate
electrochemical energy storage", Energy Environ. Sci., 2014, vol.
7, pp. 1597-1614. cited by applicant .
Bao, Z. et al., "Synthesis of porous self-supporting
metal-nanoparticle assemblies with 3D Morphologies inherited from
biosilica templates (diatom frustules)" Advanced materials, 2009,
v. 21, p. 474. cited by applicant .
Baruah, S. et al., "Hydrothermal growth of ZnO nanostructures" Sci.
Technol. Adv. Mater., 2009, 10, 013001. cited by applicant .
Cai, Y. et al., "Manganese-doped zinc orthosilicate-bearing
phosphor microparticles with controlled three-dimentional shapes
derived from diatom frustules" Journal of the American Ceramic
Society, 2007, 90(4), 1304. cited by applicant .
Choma, J. et al., "Deposition of silver nanoparticles on silica
spheres and rods" Colloids and Surfaces A: Physicochem. Eng.
Aspects, 2012, doi: 10.1016/j.colsurfa.2012.07.004. cited by
applicant .
Drum, R.W. et al, "Star Trek replicators and diatom nanotechnology"
Trends in Biotechnology, 2003, 21(8), 325. cited by applicant .
Fang, Y. et al., "Protein-mediated layer-by-layer synthesis of
freestanding microscale titania structures with biologically
assembled 3-D morphologies" Chemistry of materials, 2009, 21(24),
5704. cited by applicant .
Fang, Y. et al., "Synthesis of nanostrcutured Cu- and Ni-based
micro-asseblies with selectable 3-D hierarchical biogenic
morphologies" Journal of Materials Chemistry, 2012, 22(4), 1305.
cited by applicant .
Flores, J.C. et al., "Variations in morphologies of silver
nanoshells on silica spheres" Colloids and Surfaces A: Physicochem.
Eng. Aspects, 2008, 330, 86. cited by applicant .
Flores, J.C. et al., "Preparation of core-shell nanospheres of
silica-silver: SiO2@Ag" Journal of Non-Crystalline Solids, 2008,
354, 5435. cited by applicant .
Forsyth et al., "Ionic Liquids--An Overview," Aust. J. Chem., vol.
57, No. 2, Jan. 1, 2004, pp. 113-119. cited by applicant .
Franks, G.V. et al., "Zeta potentials and yield stresses of silica
suspensions in concentrated monovalent electrolytes: isoelectric
point shift and additional attraction" Journal of Colloid and
Interfacial Science, 2002, 249, 44. cited by applicant .
Gonzalez E. et al., "Surface Analysis of Polymers Treated by Remote
Atmospheric Pressure Plasma," Langmuir, 2010, vol. 26(5), pp.
3710-3719. cited by applicant .
Gordon, R. et al., "The Glass Menagerie: diatoms for novel
application in nanotechnology" Trends Biotechnol., 2009, v.27, p.
116. cited by applicant .
Guo et al., "Engineering of three dimensional (3-D)
diatom@TiO.sub.2@MnO.sub.2 composites with enhanced supercapacitor
performance", Electrochimica acta, 2016, vol. 190, pp. 159-167.
cited by applicant .
Greene, L.E. et al., "General route to vertical ZnO nanowire arrays
using textured ZnO seeds" Nano Lett., 2005, 5, 1231. cited by
applicant .
Gutu, T. et al., "Electron microscopy and optical characterization
of cadmium sulphide nanocrystals deposited on the patterned surface
of diatom biosilica" Journal of Nanomaterials, vol. 2009, Article
ID 860536, 7 pages, Feb. 19, 2009. cited by applicant .
He et al., "Morphology engineering of ZnO nanostructures for high
performancce supercapacitors: enhanced electrochemistry of ZnO
nanocones compared to ZnO nanowires", Nanotechnology, 2017, vol.
28, in 11 pages. cited by applicant .
Ho et al. "Direct write dispenser printing of a zinc microbattery
with an ionic liquid gel electrolyte" Journal of Micromechanics and
Microengineering 20 (2010) 104009 (9pp). cited by applicant .
Huang et al. "Graphene-based conducting inks for direct inkjet
printing of flexible conductive patterns and their applications in
electric circuits and chemical sensors" Nano Research (2011), 4(7),
675-684. cited by applicant .
Huang et al., "MnO2-based nanostructures for high-performance
supercapacitors", J. Mater. Chem. A, 2015, vol. 3, pp. 21380-21423.
cited by applicant .
Huaizhi, Cai et al., "Experimental Study on Purification of Sichuan
Miyi Diatomite", Comprehensive Utilization of Minerals, 1992, pp.
1-8. cited by applicant .
International Search Report and Written Opinion received in PCT
Application No. PCT/US2013/050949 dated Nov. 12, 2013 in 13 pages.
cited by applicant .
International Search Report and Written Opinion received in PCT
Application No. PCT/US2013/064309 dated Jan. 24, 2014 in 13 pages.
cited by applicant .
International Search Report and Written Opinion received in PCT
Application No. PCT/US2014/046910 dated Nov. 18, 2014 in 18 pages.
cited by applicant .
International Search Report and Written Opinion received in PCT
Application No. PCT/US2019/022344 dated Jul. 2, 2019 in 10 pages.
cited by applicant .
Jeffryes, C. et al., "Peptide mediated deposition of nanostructured
TiO2 into the periodic structure of diatom biosilica. Journal of
material research" 2008, 23(12), 3255. cited by applicant .
Jeffryes, C. et al., "The potential of diatom nanobiotechnology for
applications in solar cells, batteries, and electroluminescent
devices" Energy & Enviromental Science, 2011, v. 4, p. 3930.
cited by applicant .
Jian et al., "An Effective Cleaning Method for Producing Pure
Diatom Samples from Lake Sediments", Earth and Environment, 2007,
vol. 35, No. 1, pp. 91-96. cited by applicant .
Kalmychkov, G. V. et al., "Method of separation of diatom frustules
from bottom sediments for oxygen isotopic analysis and
paleoclimatic reconstruction" Geokhimiya, 2005, 12, 1358. cited by
applicant .
Kim, J. et al., "Direct synthesis and integration of functional
nanostructures in microfluidic devices" Lab on Chip, 11, p.
1946-1951, 2011. cited by applicant .
Kumar, M. et al., "Chemical vapor deposition of carbon nanotubes: a
review on growth mechanism and mass production" Journal of
Nanoscience and Nanotechnology, 2010, 10, 3739. cited by applicant
.
Le et al., Morphology-controlled MnO.sub.2 modified silicon diatoms
for high performance asymmetric supercapacitors., J. Mater. Chem.
A, 2017, vol. 5, No. 22, pp. 10856-10865. cited by applicant .
Lebeau T. et al., "Diatom cultivation and biotechnologically
relevant products. Part I: cultivation at various scales" Appl.
Microbiol. Biotechnol., 2003, 60, 612. cited by applicant .
Lee, Seung-Jin et al., "Rapid Hydrolysis of Organophosphorous
Esters Induced by Nanostructured, Flourine-Doped Titania Replicas
of Diatom Frustules" J. Am. Ceram. Soc., 90 [5], p. 1632-1636,
2007. cited by applicant .
Li, F et al., "MnO.sub.2 nanostructures with three-dimensional (3D)
morphology replicated from diatoms for high-performance
supercapacitors", J. Mater., Cham. A, 2015, vol. 3, pp. 7855-7861.
cited by applicant .
Li, H. et al., "Peptide-mediated deposition of nanostructured TiO2
into the periodic structure of diatom biosilica and its integration
into the fabrication of a dye-sensitized solar cell device"
Materials Research Society Symposium Proceedings, 2009, 1189E.
cited by applicant .
Mirkin, C.A. et al., AFOSR Final report. "Diatomeceous, fungal, and
bacterial building blocks for material synthesis" 2008. cited by
applicant .
Nassif, N. et al., "From Fiatoms to silica-based biohybrids" Chem
Soc Rev, 2011, v.40, p. 849-859. cited by applicant .
Parkinson, J. et al., "Beyond micromashinning: the potential of
diatoms" Nanotechnology. 1999, v. 17, p. 190. cited by applicant
.
Payne, E. K. et al., "Sacrificial Biolofical Templates for the
Formation of Nanostructured Metallic Microshells" Chem., Int. Ed.,
2005, v. 44, p. 5064. cited by applicant .
Peng, Yuan, "Purification of Diatomaceous Earth and its Surface
Hydroxyl and Acid Sites", Guangzhou Institute of Geochemistry,
Chinese Academy of Sciences, 2001, pp. 9. cited by applicant .
Pinkert A. et al., "Ionic Liquids and Their Interaction with
Cellulose," Chemical Reviews, 2009, vol. 109, pp. 6712-6728. cited
by applicant .
Pol, V.G. et al., "Sonochemical Deposition of Silver Nanoparticles
on Silica Spheres" Langmuir, 2002, 18, 3352. cited by applicant
.
Prout, "Aspects of lead/acid battery technology. 7. Separators"
Journal of Power Sources (1993), 46(1), 117-38. cited by applicant
.
Renberg, I. et al., "A procedure for preparing large sets of diatom
slides from sediment cores" Journal of Paleolimnology, 1990, 4, 87.
cited by applicant .
Rings, A. et al., "A new method for the quantitative separation of
diatom frustules from lake sediments" Limnology and Oceanography:
Methods, 2004, 2, 25. cited by applicant .
Round, F. E. et al., "The Diatoms: biology & morphology of the
genera" 1990. cited by applicant .
Sandhage, K. H. et al., "Novel, Bioclastic Route to Self-Assembled,
3D, Chemically Tailored Meso/Nanostructures: Shape-Preserving
Reactive Conversion of Biosilica (Diatom) Microshells" Adv. Mater.,
2002, v. 14, No. 6, p. 429-433. cited by applicant .
Sandhage, K.H. et al., "Merging biological self-assembly with
synthetic chemical tailoring: The potential for 3-D genetically
engineered micro/nano-devices (3-D GEMS)" International Journal of
Applied Ceramic Technology (2005), 2(4), 317. cited by applicant
.
Sandhage, K. et al., "Bio-enabled synthesis of functional 3-D
nanostructured materials via layer-by-layer deposition"
International Chemical Congress of Pacific Basin Societies,
Honolulu. 2010. cited by applicant .
Serieyssol, K. et al., "Diatom fossils in mires: a protocol for
extraction, preparation and analysis in palaeoenvironmental
studies" Mires and Peat, 2010, 7, 1. cited by applicant .
Shen, Lanyao et al., "Magnesiothermically reduced diatomaceous
earth as a porous silicon anode material for lithium ion batteries"
Journal of Power Sources (2012), 213, 229-232. cited by applicant
.
Shian, S. et al., "Three-Dimensional Assemblies of Zirconia
Nanocrystals via Shape-Preserving Reactive Conversion of Diatom
Microshells" J. Am. Ceram. Soc., 2006, v. 89, p. 694-698. cited by
applicant .
Shuilin, Zheng, "Studies of Purifying of Clayey Diatomite", Journal
of Wuhan University of Technology--Materials Science, 1994, No. 01,
pp. 125-133. cited by applicant .
Skipp, G.L. et al., "Improved density gradient techniques using
sodium poltungstate and a comparison to the use of other heavy
liquids" U.S. department of the Interior. U.S. Geological survey,
1993, OF 92-038. cited by applicant .
Sterrenburg, F.A.S., "How to prepare diatom samples"
micrap.selfip.com:81/micrapp/cleandiatoms.pdf, 13 pages, undated.
cited by applicant .
Sun et al., "Diatom silica, an emerging biomaterial for energy
conversion and storage", J. Mater. Chem. A, 2017, vol. 5, pp.
8847-8859. cited by applicant .
Sutto et al., "Ionic liquid batteries: Chemistry to replace
alkaline/acid energy storage devices", Electrochimica Acta, 2011,
vol. 56, pp. 3375-3379. cited by applicant .
Tang, S. et al., "Ultrasonic electrodeposition of silver
nanoparticles on dielectric silica spheres" Nanotechnology, 2007,
18, 295607. cited by applicant .
Torrisi, F. et al. "Ink-jet printed graphene electronics" Condensed
Matter (2011), 1-12, arXiv:1111.4970v1. cited by applicant .
Toster, J. et al., "Controlling anatase coating of diatom frustules
by varying the binding layer" Cryst. Eng. Comm. 2012, 14(2), 3446.
cited by applicant .
Tuval, T. et al., "A microwave-assisted polyol method for the
deposition of silver nanoparticles on silica spheres"
Nanotechnology, 2007, 18, 255601. cited by applicant .
Umemura, K. et al., "Preparation of photocatalyst using diatom
frustules by liquid phase deposition method" Journal of Nanoscience
and Nanotechnology, 2010, 10(8), 4883. cited by applicant .
Unalan, H.E. et al., "Rapid synthesis of aligned zinc oxide
nanowires" Nanotechnology, 2008, 19, 255608. cited by applicant
.
Wang, Z. et al., "Facile fabrication method and characterization of
hollow Ag/SiO2 double-shelled spheres" Langmuir, 2009, 25(13),
7646. cited by applicant .
Weatherspoon, M.R. et al., "Thin, conformal, and continues SnO2
coatings on three-dimensional biosilica templates through
hydroxyl-group amplification and layer-by-layer alkoxide
deposition" Angewandte Chemie, 2007, 46(30), 5724. cited by
applicant .
Wen et al., Morphology-controlled MnO.sub.2-graphene
oxide-diatomaceous earth 3-dimentional (3D) composites for
high-performance supercapacitors, Dalton Trans., 2016, vol. 45, pp.
936-942. cited by applicant .
Wikipedia, "Supercapacitor",
https://en.wikipedia.org/wiki/Supercapacitor, downloaded Feb. 8,
2018 in 35 pages. cited by applicant .
Xia, H. et al., "Surface synthesis of zinc oxide nanoparticles on
silica spheres: preparation and characterization" J. Phys. Chem. B,
2003, 107, 9175. cited by applicant .
Xu, S. et al., "One-dimentional ZnO nanostructures: solution growth
and functional properties" NanoRes, 2011, doi
10.1007/s12274-011-0160-7. cited by applicant .
Ye, X. et al., "Deposition of silver nanoparticles on silica
spheres via ultrasound irradiation" Applied Surface Science, 2007,
253, 6264. cited by applicant .
Yu, Y. et al., "Surface modification of diatomaceous earth silica
microparticles with functional silanes for metal ions sorption"
CHEMECA. Sep. 26-29, 2010, Adelaide, Australia. cited by applicant
.
Zhang et al., "Hierarchical NiO moss decorated diatomites via
facile and templated method for high performance supercapacitors",
Materials Letters, 2014, vol. 120, pp. 263-266. cited by applicant
.
Zhang et al. "One-pot synthesis of hierarchical MnO2-modified
diatomites for electromechanical capacitor electrodes" Journal of
Power Sources, vol. 246, Aug. 6, 2013, pp. 449-456. cited by
applicant .
Zhang, Y. et al., "Synthesis, characterization, and applications of
ZnO nanowires" Journal of Nanomaterials, 2012, doi:
10.1155/2012/624520. cited by applicant .
Zheng, S. et al., "Preparation and Photocatalytic Property of
TiO2/Diatomite-Based Porous Ceramics Composite Materials"
International Journal of Photoenergy, vol. 2012, Article ID 264186,
pp. 1-4, 2011. cited by applicant .
Zhuravlev, "The surface chemistry of amorphous silica. Zhuravlev
model" Colloids and Surfaces A: Physicochemical and Engineering
Aspects, 2000, 173, 1. cited by applicant.
|
Primary Examiner: Kelly; Cynthia H
Assistant Examiner: Wills; Monique M
Attorney, Agent or Firm: Knobbe, Martens, Olson & Bear,
LLP
Parent Case Text
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser.
No. 15/926,896, filed Mar. 20, 2018, entitled "Diatomaceous Energy
Storage Devices," which is a continuation-in-part of U.S. patent
application Ser. No. 15/808,757, filed Nov. 9, 2017, entitled
"Diatomaceous Energy Storage Devices," which is a continuation of
U.S. patent application Ser. No. 15/406,407, filed Jan. 13, 2017,
entitled "Diatomaceous Energy Storage Devices," which is a
continuation of U.S. patent application Ser. No. 14/745,709, filed
Jun. 22, 2015, entitled "Diatomaceous Energy Storage Devices,"
which is continuation-in-part of U.S. patent application Ser. No.
14/161,658, filed Jan. 22, 2014, entitled "Diatomaceous Energy
Storage Devices," which claims the benefit of U.S. Provisional
Patent Application Ser. No. 61/862,469, filed Aug. 5, 2013,
entitled "High Surface Area Nanoporous Energy Storage Devices," and
which is a continuation-in-part of U.S. patent application Ser. No.
13/944,211, filed Jul. 17, 2013, entitled "Diatomaceous Energy
Storage Devices," which claims the benefit of U.S. Provisional
Patent Application Ser. No. 61/750,757, filed Jan. 9, 2013,
entitled "Diatomaceous Energy Storage Devices," and U.S.
Provisional Patent Application Ser. No. 61/673,149, filed Jul. 18,
2012, entitled "Diatomaceous Energy Storage Devices," each of which
is incorporated herein by reference in its entirety.
Claims
What is claimed is:
1. A supercapacitor comprising: a pair of electrodes contacting an
electrolyte, wherein each of the electrodes comprises a plurality
of frustules having formed thereon a manganese oxide, and wherein
the supercapacitor is configured to charge and discharge through an
electrochemical process.
2. The supercapacitor of claim 1, wherein the frustules of one or
both of the electrodes further have formed thereon a zinc
oxide.
3. The supercapacitor of claim 1, wherein the frustules of one or
both of the electrodes have formed thereon nanostructures
comprising the manganese oxide.
4. The supercapacitor of claim 1, wherein the manganese oxide
comprises one or more of manganese dioxide (MnO.sub.2), manganese
(II, III) oxide (Mn.sub.3O.sub.4), manganese(II) oxide (MnO), or
manganese (III) oxide (Mn.sub.2O.sub.3).
5. The supercapacitor of claim 1, wherein each of the electrodes is
configured as a pseudo capacitor.
6. The supercapacitor of claim 1, wherein no ion transport occurs
between the one of the electrodes and the other of the electrodes
as part of an electrochemical reaction during charge or
discharge.
7. The supercapacitor of claim 1, wherein the electrolyte comprises
an ionic liquid.
8. The supercapacitor of claim 7, wherein the ionic liquid
comprises one or more cations selected from the group consisting of
butyltrimethylammonium, 1-ethyl-3-methylimidazolium,
1-butyl-3-methylimidazolium, 1-methyl-3-propylimidazolium,
1-hexyl-3-methylimidazolium, choline, ethylammonium,
tributylmethylphosphonium, tributyl(tetradecyl)phosphonium,
trihexyl(tetradecyl)phosphonium, 1-ethyl-2,3-methylimidazolium,
1-butyl-1-methylpiperidinium, diethylmethylsulfonium,
1-methyl-3-propylimidazolium, 1-ethyl-3-methylimidazolium,
1-methyl-1-propylpiperidinium, 1-butyl-2-methylpyridinium,
1-butyl-4-methylpyridinium, 1-butyl-1-methylpyrrolidinium,
diethylmethylsulfonium or a combination thereof.
9. The supercapacitor of claim 7, wherein the ionic liquid
comprises or more anions selected from the group consisting of
tris(pentafluoroethyl)trifluorophosphate,
trifluoromethanesulfonate, hexafluorophosphate, tetrafluoroborate,
ethyl sulfate, dimethyl phosphate, methanesulfonate, triflate,
tricyanomethanide, dibutylphosphate,
bis(trifluoromethylsulfonyl)imide, bis-2,4,4-(trimethylpentyl)
phosphinate, iodide, chloride, bromide, nitrate or a combination
thereof.
10. A supercapacitor comprising: a pair of electrodes contacting an
electrolyte, wherein each of the electrodes comprises a plurality
of frustules having formed thereon a zinc oxide, and wherein the
supercapacitor is configured to charge and discharge through an
electrochemical process.
11. The supercapacitor of claim 10, wherein the frustules of one or
both of the electrodes further have formed thereon a manganese
oxide.
12. The supercapacitor of claim 10, wherein the frustules of one or
both of the electrodes have formed thereon nanostructures
comprising the zinc oxide.
13. The supercapacitor of claim 11, wherein the manganese oxide
comprises one or more of manganese dioxide (MnO.sub.2), manganese
(II, III) oxide (Mn.sub.3O.sub.4), manganese (II) oxide (MnO), or
manganese(III) oxide (Mn.sub.2O.sub.3).
14. The supercapacitor of claim 10, wherein each of the electrodes
is configured as a pseudo capacitor.
15. The supercapacitor of claim 10, wherein no ion transport occurs
between the one of the electrodes and the other of the electrodes
as part of an electrochemical reaction during charge or
discharge.
16. A supercapacitor comprising: a first electrode comprising a
plurality of frustules having formed thereon one or both a
manganese oxide and a zinc oxide; and a second electrode comprising
carbon nanotubes, wherein the supercapacitor is configured to
charge and discharge through an electrochemical process.
17. The supercapacitor of claim 16, wherein the first electrode is
configured as a pseudocapacitor and the second electrode is
configured as an electric double-layer capacitor.
18. The supercapacitor of claim 16, wherein the first electrode and
the second electrode contact a non-aqueous electrolyte.
19. The supercapacitor of claim 16, wherein the manganese oxide
comprises one or more of manganese dioxide (MnO.sub.2), manganese
(II, III) oxide (Mn.sub.3O.sub.4), manganese(II) oxide (MnO), or
manganese (III) oxide (Mn.sub.2O.sub.3).
20. The supercapacitor of claim 16, wherein no ion transport occurs
between the one of the electrodes and the other of the electrodes
as part of an electrochemical reaction during charge or discharge.
Description
BACKGROUND
Field
The present application relates to energy storage devices, and
particularly to energy storage devices comprising frustules of
diatoms.
Description of the Related Art
Diatoms typically include unicellular eukaryotes, such as
single-celled algae. Diatoms are abundant in nature and can be
found in both fresh water and marine environments. Generally,
diatoms are enclosed by a frustule having two valves fitted
together through a connective zone comprising girdle elements.
Diatomaceous earth, sometimes known as diatomite, can be a source
of frustules. Diatomaceous earth comprises fossilized frustules and
can be used in a diverse range of applications, including as a
filtering agent, a filling agent for paints or plastics, an
adsorbent, cat litter, or an abrasive material.
Frustules often comprise a significant amount of silica
(SiO.sub.2), along with alumina, iron oxide, titanium oxide,
phosphate, lime, sodium, and/or potassium. Frustules are typically
electrically insulating. Frustules may comprise a wide variety of
dimensions, surface features, shapes, and other attributes. For
example, frustules may comprise diverse shapes, including but not
limited to cylinders, spheres, discs, or prisms. Frustules comprise
a symmetrical shape or a non-symmetrical shape. Diatoms may be
categorized according to the shape and/or symmetry of the
frustules, for example grouping the diatoms based on existence or
lack of radial symmetry. Frustules may comprise dimensions within a
range from less than about one micron to about hundreds of microns.
Frustules may also comprise varying porosity, having numerous pores
or slits. Pores or slits of frustules may vary in shape, size,
and/or density. For example, frustules may comprise pores having
dimensions from about 5 nm to about 1000 nm.
Frustules may comprise significant mechanical strength or
resistance to shear stress, for example due to the dimensions of
the frustule, frustule shape, porosity, and/or material
composition.
SUMMARY
An energy storage device such as a battery (e.g., rechargeable
battery), fuel cell, capacitor, and/or supercapacitor (e.g.,
electric double-layer capacitor (EDLC), pseudo capacitor, symmetric
capacitor), may be fabricated using frustules embedded in at least
one layer of the energy storage device. The frustules can be sorted
to have a selected shape, dimension, porosity, material, surface
feature, and/or another suitable frustule attribute, which may be
uniform or substantially uniform or which may vary. The frustules
may include a frustule surface modifying structure and/or material.
The energy storage device may include layers such as electrodes,
separators, and/or current collectors. For example, a separator may
be positioned between a first electrode and a second electrode, a
first current collector may be coupled to the first electrode, and
a second current collector may be coupled to the second electrode.
At least one of the separator, the first electrode, and the second
electrode may include the frustules. Inclusion of frustules in at
least a portion of an energy storage device can help to fabricate
the energy storage device using printing technology, including
screen printing, roll-to-roll printing, ink-jet printing, and/or
another suitable printing process. The frustules can provide
structural support for an energy storage device layer and help the
energy storage device layer to maintain a uniform or substantially
uniform thickness during manufacturing and/or use. Porous frustules
can allow unimpeded or substantially unimpeded flow of electrons or
ionic species. Frustules including surface structures or material
can increase conductivity of a layer.
In some embodiments, a printed energy storage device comprises a
first electrode, a second electrode, and a separator between the
first electrode and the second electrode. At least one of the first
electrode, the second electrode, and the separator includes
frustules.
In some embodiments, the separator includes the frustules. In some
embodiments, the first electrode includes the frustules. In some
embodiments, the separator and the first electrode include the
frustules. In some embodiments, the second electrode includes the
frustules. In some embodiments, the separator and the second
electrode include the frustules. In some embodiments, the first
electrode and the second electrode include the frustules. In some
embodiments, the separator, the first electrode, and the second
electrode include the frustules.
In some embodiments, the frustules have a substantially uniform
property. In some embodiments, the property comprises shape, for
example including a cylinder, a sphere, a disc, or a prism. In some
embodiments, the property comprises a dimension, for example
including diameter, length, or a longest axis. In some embodiments,
the property comprises porosity. In some embodiments, the property
comprises mechanical strength.
In some embodiments, the frustules comprise a surface modifying
structure. In some embodiments, the surface modifying structure
includes a conductive material. In some embodiments, the conductive
material includes at least one of silver, aluminum, tantalum,
copper, lithium, magnesium, and brass. In some embodiments, the
surface modifying structure includes zinc oxide (ZnO). In some
embodiments, the surface modifying structure comprises a
semiconductor. In some embodiments, the semiconductor includes at
least one of silicon, germanium, silicon germanium, and gallium
arsenide. In some embodiments, the surface modifying structure
comprises at least one of a nanowire, a nanoparticle, and a
structure having a rosette shape. In some embodiments, the surface
modifying structure is on an exterior surface of the frustules. In
some embodiments, the surface modifying structure is on an interior
surface of the frustules. In some embodiments, the surface
modifying structure is on an interior surface and an exterior
surface of the frustules.
In some embodiments, the frustules comprise a surface modifying
material. In some embodiments, the surface modifying material
comprises a conductive material. In some embodiments, the surface
modifying material includes at least one of silver, aluminum,
tantalum, copper, lithium, magnesium, and brass. In some
embodiments, the surface modifying material includes ZnO. In some
embodiments, the surface modifying material includes a
semiconductor. In some embodiments, the semiconductor includes at
least one of silicon, germanium, silicon germanium, and gallium
arsenide. In some embodiments, the surface modifying material is on
an exterior surface of the frustules. In some embodiments, the
surface modifying material is on an interior surface of the
frustules. In some embodiments, the surface modifying material is
on an exterior surface and an interior surface of the
frustules.
In some embodiments, the first electrode comprises a conductive
filler. In some embodiments, the second electrode comprises a
conductive filler. In some embodiments, the first electrode and the
second electrode comprise a conductive filler. In some embodiments,
the conductive filler comprises graphitic carbon. In some
embodiments, the conductive filler comprises graphene. In some
embodiments, the conductive filler comprises carbon nanotubes.
In some embodiments, the first electrode comprises an adherence
material. In some embodiments, the second electrode comprises an
adherence material. In some embodiments, the first electrode and
the second electrode comprise an adherence material. In some
embodiments, the separator comprises an adherence material. In some
embodiments, the first electrode and the separator comprise an
adherence material. In some embodiments, the second electrode and
the separator comprise an adherence material. In some embodiments,
the first electrode, the second electrode, and the separator
comprise an adherence material. In some embodiments, the adherence
material comprises a polymer.
In some embodiments, the separator comprises an electrolyte. In
some embodiments, the electrolyte comprises at least one of an
ionic liquid, an acid, a base, and a salt. In some embodiments, the
electrolyte comprises an electrolytic gel.
In some embodiments, the device comprises a first current collector
in electrical communication with the first electrode. In some
embodiments, the device comprises a second current collector in
electrical communication with the second electrode. In some
embodiments, the device comprises a first current collector in
electrical communication with the first electrode and a second
current collector in electrical communication with the second
electrode.
In some embodiments, the printed energy storage device comprises a
capacitor. In some embodiments, the printed energy storage device
comprises a supercapacitor. In some embodiments, the printed energy
storage device comprises a battery.
In some embodiments, a system comprises a plurality of the printed
energy storage devices as described herein stacked on top of each
other. In some embodiments, an electrical device comprises the
printed energy storage devices described herein or the system.
In some embodiments, a membrane for a printed energy storage device
comprises frustules.
In some embodiments, the frustules have a substantially uniform
property. In some embodiments, the property comprises shape, for
example including a cylinder, a sphere, a disc, or a prism. In some
embodiments, the property comprises a dimension, for example
including diameter, length, or a longest axis. In some embodiments,
the property comprises porosity. In some embodiments, the property
comprises mechanical strength.
In some embodiments, the frustules comprise a surface modifying
structure. In some embodiments, the surface modifying structure
includes a conductive material. In some embodiments, the conductive
material includes at least one of silver, aluminum, tantalum,
copper, lithium, magnesium, and brass. In some embodiments, the
surface modifying structure includes zinc oxide (ZnO). In some
embodiments, the surface modifying structure comprises a
semiconductor. In some embodiments, the semiconductor includes at
least one of silicon, germanium, silicon germanium, and gallium
arsenide. In some embodiments, the surface modifying structure
comprises at least one of a nanowire, a nanoparticle, and a
structure having a rosette shape. In some embodiments, the surface
modifying structure is on an exterior surface of the frustules. In
some embodiments, the surface modifying structure is on an interior
surface of the frustules. In some embodiments, the surface
modifying structure is on an interior surface and an exterior
surface of the frustules.
In some embodiments, the frustules comprise a surface modifying
material. In some embodiments, the surface modifying material
comprises a conductive material. In some embodiments, the surface
modifying material includes at least one of silver, aluminum,
tantalum, copper, lithium, magnesium, and brass. In some
embodiments, the surface modifying material includes ZnO. In some
embodiments, the surface modifying material includes a
semiconductor. In some embodiments, the semiconductor includes at
least one of silicon, germanium, silicon germanium, and gallium
arsenide. In some embodiments, the surface modifying material is on
an exterior surface of the frustules. In some embodiments, the
surface modifying material is on an interior surface of the
frustules. In some embodiments, the surface modifying material is
on an exterior surface and an interior surface of the
frustules.
In some embodiments, the membrane further comprises a conductive
filler. In some embodiments, the conductive filler comprises
graphitic carbon. In some embodiments, the conductive filler
comprises graphene.
In some embodiments, the membrane further comprises an adherence
material. In some embodiments, the adherence material comprises a
polymer.
In some embodiments, the membrane further comprises an electrolyte.
In some embodiments, the electrolyte comprises at least one of an
ionic liquid, an acid, a base, and a salt. In some embodiments, the
electrolyte comprises an electrolytic gel.
In some embodiments, an energy storage device comprises the
membrane as described herein. In some embodiments, the printed
energy storage device comprises a capacitor. In some embodiments,
the printed energy storage device comprises a supercapacitor. In
some embodiments, the printed energy storage device comprises a
battery. In some embodiments, a system comprises a plurality of
energy storage devices as described herein stacked on top of each
other. In some embodiments, an electrical device comprises the
printed energy storage devices described herein or the system.
In some embodiments, a method of manufacturing a printed energy
storage device comprises forming a first electrode, forming a
second electrode, and forming a separator between the first
electrode and the second electrode. At least one of the first
electrode, the second electrode, and the separator includes
frustules.
In some embodiments, the separator includes the frustules. In some
embodiments, forming the separator includes forming a dispersion of
the frustules. In some embodiments, forming the separator includes
screen printing the separator. In some embodiments, forming the
separator includes forming a membrane of the frustules. In some
embodiments, forming the separator includes roll-to-roll printing
the membrane including the separator.
In some embodiments, the first electrode includes the frustules. In
some embodiments, forming the first electrode includes forming a
dispersion of the frustules. In some embodiments, forming the first
electrode includes screen printing the first electrode. In some
embodiments, forming the first electrode includes forming a
membrane of the frustules. In some embodiments, forming the first
electrode includes roll-to-roll printing the membrane including the
first electrode.
In some embodiments, the second electrode includes the frustules.
In some embodiments, forming the second electrode includes forming
a dispersion of the frustules. In some embodiments, forming the
second electrode includes screen printing the second electrode. In
some embodiments, forming the second electrode includes forming a
membrane of the frustules. In some embodiments, forming the second
electrode includes roll-to-roll printing the membrane including the
second electrode.
In some embodiments, the method further comprises sorting the
frustules according to a property. In some embodiments, the
property comprises at least one of shape, dimension, material, and
porosity.
In some embodiments, an ink comprises a solution and frustules
dispersed in the solution.
In some embodiments, the frustules have a substantially uniform
property. In some embodiments, the property comprises shape, for
example including a cylinder, a sphere, a disc, or a prism. In some
embodiments, the property comprises a dimension, for example
including diameter, length, or a longest axis. In some embodiments,
the property comprises porosity. In some embodiments, the property
comprises mechanical strength.
In some embodiments, the frustules comprise a surface modifying
structure. In some embodiments, the surface modifying structure
includes a conductive material. In some embodiments, the conductive
material includes at least one of silver, aluminum, tantalum,
copper, lithium, magnesium, and brass. In some embodiments, the
surface modifying structure includes zinc oxide (ZnO). In some
embodiments, the surface modifying structure comprises a
semiconductor. In some embodiments, the semiconductor includes at
least one of silicon, germanium, silicon germanium, and gallium
arsenide. In some embodiments, the surface modifying structure
comprises at least one of a nanowire, a nanoparticle, and a
structure having a rosette shape. In some embodiments, the surface
modifying structure is on an exterior surface of the frustules. In
some embodiments, the surface modifying structure is on an interior
surface of the frustules. In some embodiments, the surface
modifying structure is on an interior surface and an exterior
surface of the frustules.
In some embodiments, the frustules comprise a surface modifying
material. In some embodiments, the surface modifying material
comprises a conductive material. In some embodiments, the surface
modifying material includes at least one of silver, aluminum,
tantalum, copper, lithium, magnesium, and brass. In some
embodiments, the surface modifying material includes ZnO. In some
embodiments, the surface modifying material includes a
semiconductor. In some embodiments, the semiconductor includes at
least one of silicon, germanium, silicon germanium, and gallium
arsenide. In some embodiments, the surface modifying material is on
an exterior surface of the frustules. In some embodiments, the
surface modifying material is on an interior surface of the
frustules. In some embodiments, the surface modifying material is
on an exterior surface and an interior surface of the
frustules.
In some embodiments, the ink further comprises a conductive filler.
In some embodiments, the conductive filler comprises graphitic
carbon. In some embodiments, the conductive filler comprises
graphene.
In some embodiments, the ink further comprises an adherence
material. In some embodiments, the adherence material comprises a
polymer.
In some embodiments, the ink further comprises an electrolyte. In
some embodiments, the electrolyte comprises at least one of an
ionic liquid, an acid, a base, and a salt. In some embodiments, the
electrolyte comprises an electrolytic gel.
In some embodiments, a device comprises at least one of the inks
described herein. In some embodiments, the device comprises a
printed energy storage device. In some embodiments, the printed
energy storage device comprises a capacitor. In some embodiments,
the printed energy storage device comprises a supercapacitor. In
some embodiments, the printed energy storage device comprises a
battery.
A method of extracting a diatom frustule portion may comprise
dispersing a plurality of diatom frustule portions in a dispersing
solvent. At least one of an organic contaminant and an inorganic
contaminant may be removed. The method of extracting a diatom
frustule portion may comprise dispersing the plurality of diatom
frustule portions in a surfactant, the surfactant reducing an
agglomeration of the plurality of diatom frustule portions. The
method may comprise extracting a plurality of diatom frustule
portions having at least one common characteristic using a disc
stack centrifuge.
In some embodiments, the at least one common characteristic can
include at least one of a dimension, a shape, a material, and a
degree of brokenness. The dimension may include at least one of a
length and a diameter.
In some embodiments, a solid mixture can comprise the plurality of
diatom frustule portions. The method of extracting a diatom
frustule portion may comprise reducing a particle dimension of the
solid mixture. Reducing the particle dimension of the solid mixture
may be before dispersing the plurality of diatom frustule portions
in the dispersing solvent. In some embodiments, reducing the
particle dimension can comprise grinding the solid mixture.
Grinding the solid mixture may include applying to the solid
mixture at least one of a mortar and a pestle, a jar mill, and a
rock crusher.
In some embodiments, a component of the solid mixture having a
longest component dimension that is greater than a longest frustule
portion dimension of the plurality of diatom frustule portions can
be extracted. Extracting the component of the solid mixture may
comprise sieving the solid mixture. Sieving the solid mixture may
comprise processing the solid mixture with a sieve having a mesh
size from about 15 microns to about 25 microns. Sieving the solid
mixture may comprise processing the solid mixture with a sieve
having a mesh size from about 10 microns to about 25 microns.
In some embodiments, the method of extracting a diatom frustule
portion can comprise sorting the plurality of diatom frustule
portions to separate a first diatom frustule portion from a second
diatom frustule portion, the first diatom frustule portion having a
greater longest dimension. For example, the first diatom frustule
portion may comprise a plurality of unbroken diatom frustule
portions. The second diatom frustule portion may comprise a
plurality of broken diatom frustule portions.
In some embodiments, sorting the plurality of diatom frustule
portions can comprise filtering the plurality of diatom frustule
portions. Filtering may comprise disturbing agglomeration of the
plurality of diatom frustule portions. In some embodiments,
disturbing agglomeration of the plurality of diatom frustule
portions can comprise stirring. In some embodiments, disturbing
agglomeration of the plurality of diatom frustule portions can
comprise shaking. In some embodiments, disturbing agglomeration of
the plurality of diatom frustule portions can comprise
bubbling.
Filtering may include applying a sieve to the plurality of diatom
frustule portions. For example, the sieve may have a mesh size from
about 5 microns to about 10 microns, including about 7 microns.
In some embodiments, the method of extracting a diatom frustule
portion can include obtaining a washed diatom frustule portion.
Obtaining the washed diatom frustule portion may comprise washing
the plurality of diatom frustule portions with a cleaning solvent
after removing the at least one of the organic contaminant and the
inorganic contaminant. In some embodiments, obtaining the washed
diatom frustule portion can comprise washing the diatom frustule
portion having the at least one common characteristic with a
cleaning solvent.
The cleaning solvent may be removed. For example, removing the
cleaning solvent may comprise sedimenting the plurality of diatom
frustule portions after removing at least one of the organic
contaminant and the inorganic contaminant. For example, removing
the cleaning solvent may comprise sedimenting the plurality of
diatom frustule portions having the at least one common
characteristic. Sedimenting the plurality of diatom frustule
portions may comprise centrifuging. In some embodiments,
centrifuging can comprise applying a centrifuge suitable for large
scale processing. In some embodiments, centrifuging can comprise
applying at least one of a disc stack centrifuge, a decanter
centrifuge, and a tubular bowl centrifuge.
In some embodiments, at least one of the dispersing solvent and the
cleaning solvent can comprise water.
In some embodiments, at least one of dispersing the plurality of
diatom frustule portions in the dispersing solvent and dispersing
the plurality of diatom frustule portions in the surfactant can
comprise sonicating the plurality of diatom frustules.
The surfactant may comprise a cationic surfactant. For example, the
cationic surfactant may comprise at least one of a benzalkonium
chloride, a cetrimonium bromide, a lauryl methyl gluceth-10
hydroxypropyl dimonium chloride, a benzethonium chloride, a
benzethonium chloride, a bronidox, a dmethyldioctadecylammonium
chloride, and a tetramethylammonium hydroxide.
The surfactant may comprise a non-ionic surfactant. For example,
the non-ionic surfactant may comprise at least one of a cetyl
alcohol, a stearyl alcohol, a cetostearyl alcohol, an oleyl
alcohol, a polyoxyethylene glycol alkyl ether, an octaethylene
glycol monododecyl ether, a glucoside alkyl ethers, a decyl
glucoside, a polyoxyethylene glycol octylphenol ethers, an
octylphenol ethoxylate (Triton X-100.TM.), a nonoxynol-9, a
glyceryl laurate, a polysorbate, and a poloxamer.
In some embodiments, the method of extracting a diatom frustule
portion can comprise dispersing the plurality of diatom frustules
in an additive component. Dispersing the plurality of diatom
frustules in an additive component may be before dispersing the
plurality of diatom frustules in the surfactant. Dispersing the
plurality of diatom frustules in an additive component may be after
dispersing the plurality of diatom frustules in the surfactant.
Dispersing the plurality of diatom frustules in an additive
component may be at least partially simultaneous with dispersing
the plurality of diatom frustules in the surfactant. The additive
component may include at least one of a potassium chloride, an
ammonium chloride, an ammonium hydroxide, and a sodium
hydroxide.
In some embodiments, dispersing the plurality of diatom frustule
portions can comprise obtaining a dispersion comprising about 1
weight percent to about 5 weight percent of the plurality of diatom
frustule portions.
In some embodiments, removing the organic contaminant can comprise
heating the plurality of diatom frustule portions in the presence
of a bleach. The bleach may include at least one of a hydrogen
peroxide and a nitric acid. Heating the plurality of diatom
frustule portions may comprise heating the plurality of diatom
frustule portions in a solution comprising an amount of hydrogen
peroxide in a range from about 10 volume percent to about 20 volume
percent. Heating the plurality of diatom frustule portions may
comprise heating the plurality of diatom frustule portions for a
duration of about 5 minutes to about 15 minutes.
In some embodiments, removing the organic contaminant can comprise
annealing the plurality of diatom frustule portions. In some
embodiments, removing the inorganic contaminant can comprise
combining the plurality of diatom frustule portions with at least
one of a hydrochloric acid and a sulfuric acid. Combining the
plurality of diatom frustule portions with at least one of a
hydrochloric acid and a sulfuric acid may include mixing the
plurality of diatom frustule portions in a solution comprising
about 15 volume percent to about 25 volume percent of hydrochloric
acid. For example, the mixing may be for a duration of about 20
minutes to about 40 minutes.
A method of extracting a diatom frustule portion may include
extracting a plurality of diatom frustule portions having at least
one common characteristic using a disc stack centrifuge.
In some embodiments, the method of extracting a diatom frustule
portion can comprise dispersing the plurality of diatom frustule
portions in a dispersing solvent. In some embodiments, the method
can comprise removing at least one of an organic contaminant and an
inorganic contaminant. In some embodiments, the method can comprise
dispersing the plurality of diatom frustule portions in a
surfactant, the surfactant reducing an agglomeration of the
plurality of diatom frustule portions.
The at least one common characteristic may include at least one of
a dimension, a shape, a material, and a degree of brokenness. The
dimension may include at least one of a length and a diameter.
In some embodiments, a solid mixture can comprise the plurality of
diatom frustule portions. The method of extracting a diatom
frustule portion may comprise reducing a particle dimension of the
solid mixture. Reducing the particle dimension of the solid mixture
may be before dispersing the plurality of diatom frustule portions
in the dispersing solvent. In some embodiments, reducing the
particle dimension can comprise grinding the solid mixture.
Grinding the solid mixture may include applying to the solid
mixture at least one of a mortar and a pestle, a jar mill, and a
rock crusher.
In some embodiments, a component of the solid mixture having a
longest component dimension that is greater than a longest frustule
portion dimension of the plurality of diatom frustule portions can
be extracted. Extracting the component of the solid mixture may
comprise sieving the solid mixture. Sieving the solid mixture may
comprise processing the solid mixture with a sieve having a mesh
size from about 15 microns to about 25 microns. Sieving the solid
mixture may comprise processing the solid mixture with a sieve
having a mesh size from about 10 microns to about 25 microns.
In some embodiments, the method of extracting a diatom frustule
portion can comprise sorting the plurality of diatom frustule
portions to separate a first diatom frustule portion from a second
diatom frustule portion, the first diatom frustule portion having a
greater longest dimension. For example, the first diatom frustule
portion may comprise a plurality of unbroken diatom frustule
portions. The second diatom frustule portion may comprise a
plurality of broken diatom frustule portions.
In some embodiments, sorting the plurality of diatom frustule
portions can comprise filtering the plurality of diatom frustule
portions. Filtering may comprise disturbing agglomeration of the
plurality of diatom frustule portions. In some embodiments,
disturbing agglomeration of the plurality of diatom frustule
portions can comprise stirring. In some embodiments, disturbing
agglomeration of the plurality of diatom frustule portions can
comprise shaking. In some embodiments, disturbing agglomeration of
the plurality of diatom frustule portions can comprise
bubbling.
Filtering may include applying a sieve to the plurality of diatom
frustule portions. For example, the sieve may have a mesh size from
about 5 microns to about 10 microns, including about 7 microns.
In some embodiments, the method of extracting a diatom frustule
portion can include obtaining a washed diatom frustule portion.
Obtaining the washed diatom frustule portion may comprise washing
the plurality of diatom frustule portions with a cleaning solvent
after removing the at least one of the organic contaminant and the
inorganic contaminant. In some embodiments, obtaining the washed
diatom frustule portion can comprise washing the diatom frustule
portion having the at least one common characteristic with a
cleaning solvent.
The cleaning solvent may be removed. For example, removing the
cleaning solvent may comprise sedimenting the plurality of diatom
frustule portions after removing at least one of the organic
contaminant and the inorganic contaminant. For example, removing
the cleaning solvent may comprise sedimenting the plurality of
diatom frustule portions having the at least one common
characteristic. Sedimenting the plurality of diatom frustule
portions may comprise centrifuging. In some embodiments,
centrifuging can comprise applying a centrifuge suitable for large
scale processing. In some embodiments, centrifuging can comprise
applying at least one of a disc stack centrifuge, a decanter
centrifuge, and a tubular bowl centrifuge.
In some embodiments, at least one of the dispersing solvent and the
cleaning solvent can comprise water.
In some embodiments, at least one of dispersing the plurality of
diatom frustule portions in the dispersing solvent and dispersing
the plurality of diatom frustule portions in the surfactant can
comprise sonicating the plurality of diatom frustules.
The surfactant may comprise a cationic surfactant. For example, the
cationic surfactant may comprise at least one of a benzalkonium
chloride, a cetrimonium bromide, a lauryl methyl gluceth-10
hydroxypropyl dimonium chloride, a benzethonium chloride, a
benzethonium chloride, a bronidox, a dimethyldioctadecylammonium
chloride, and a tetramethylammonium hydroxide.
The surfactant may comprise a non-ionic surfactant. For example,
the non-ionic surfactant may comprise at least one of a cetyl
alcohol, a stearyl alcohol, a cetostearyl alcohol, an oleyl
alcohol, a polyoxyethylene glycol alkyl ether, an octaethylene
glycol monododecyl ether, a glucoside alkyl ethers, a decyl
glucoside, a polyoxyethylene glycol octylphenol ethers, an
octylphenol ethoxylate (Triton X-100.TM.), a nonoxynol-9, a
glyceryl laurate, a polysorbate, and a poloxamer.
In some embodiments, the method of extracting a diatom frustule
portion can comprise dispersing the plurality of diatom frustules
in an additive component. Dispersing the plurality of diatom
frustules in an additive component may be before dispersing the
plurality of diatom frustules in the surfactant. Dispersing the
plurality of diatom frustules in an additive component may be after
dispersing the plurality of diatom frustules in the surfactant.
Dispersing the plurality of diatom frustules in an additive
component may be at least partially simultaneous with dispersing
the plurality of diatom frustules in the surfactant. The additive
component may include at least one of a potassium chloride, an
ammonium chloride, an ammonium hydroxide, and a sodium
hydroxide.
In some embodiments, dispersing the plurality of diatom frustule
portions can comprise obtaining a dispersion comprising about 1
weight percent to about 5 weight percent of the plurality of diatom
frustule portions.
In some embodiments, removing the organic contaminant can comprise
heating the plurality of diatom frustule portions in the presence
of a bleach. The bleach may include at least one of a hydrogen
peroxide and a nitric acid. Heating the plurality of diatom
frustule portions may comprise heating the plurality of diatom
frustule portions in a solution comprising an amount of hydrogen
peroxide in a range from about 10 volume percent to about 20 volume
percent. Heating the plurality of diatom frustule portions may
comprise heating the plurality of diatom frustule portions for a
duration of about 5 minutes to about 15 minutes.
In some embodiments, removing the organic contaminant can comprise
annealing the plurality of diatom frustule portions. In some
embodiments, removing the inorganic contaminant can comprise
combining the plurality of diatom frustule portions with at least
one of a hydrochloric acid and a sulfuric acid. Combining the
plurality of diatom frustule portions with at least one of a
hydrochloric acid and a sulfuric acid may include mixing the
plurality of diatom frustule portions in a solution comprising
about 15 volume percent to about 25 volume percent of hydrochloric
acid. For example, the mixing may be for a duration of about 20
minutes to about 40 minutes.
A method of extracting a diatom frustule portion may include
dispersing a plurality of diatom frustule portions with a
surfactant, the surfactant reducing an agglomeration of the
plurality of diatom frustule portions.
The method of extracting a diatom frustule portion may include
extracting a plurality of diatom frustule portions having at least
one common characteristic using a disc stack centrifuge. In some
embodiments, the method of extracting a diatom frustule portion can
comprise dispersing a plurality of diatom frustule portions in a
dispersing solvent. In some embodiments, at least one of an organic
contaminant and an inorganic contaminant may be removed.
In some embodiments, the at least one common characteristic can
include at least one of a dimension, a shape, a material, and a
degree of brokenness. The dimension may include at least one of a
length and a diameter.
In some embodiments, a solid mixture can comprise the plurality of
diatom frustule portions. The method of extracting a diatom
frustule portion may comprise reducing a particle dimension of the
solid mixture. Reducing the particle dimension of the solid mixture
may be before dispersing the plurality of diatom frustule portions
in the dispersing solvent. In some embodiments, reducing the
particle dimension can comprise grinding the solid mixture.
Grinding the solid mixture may include applying to the solid
mixture at least one of a mortar and a pestle, a jar mill, and a
rock crusher.
In some embodiments, a component of the solid mixture having a
longest component dimension that is greater than a longest frustule
portion dimension of the plurality of diatom frustule portions can
be extracted. Extracting the component of the solid mixture may
comprise sieving the solid mixture. Sieving the solid mixture may
comprise processing the solid mixture with a sieve having a mesh
size from about 15 microns to about 25 microns. Sieving the solid
mixture may comprise processing the solid mixture with a sieve
having a mesh size from about 10 microns to about 25 microns.
In some embodiments, the method of extracting a diatom frustule
portion can comprise sorting the plurality of diatom frustule
portions to separate a first diatom frustule portion from a second
diatom frustule portion, the first diatom frustule portion having a
greater longest dimension. For example, the first diatom frustule
portion may comprise a plurality of unbroken diatom frustule
portions. The second diatom frustule portion may comprise a
plurality of broken diatom frustule portions.
In some embodiments, sorting the plurality of diatom frustule
portions can comprise filtering the plurality of diatom frustule
portions. Filtering may comprise disturbing agglomeration of the
plurality of diatom frustule portions. In some embodiments,
disturbing agglomeration of the plurality of diatom frustule
portions can comprise stirring. In some embodiments, disturbing
agglomeration of the plurality of diatom frustule portions can
comprise shaking. In some embodiments, disturbing agglomeration of
the plurality of diatom frustule portions can comprise
bubbling.
Filtering may include applying a sieve to the plurality of diatom
frustule portions. For example, the sieve may have a mesh size from
about 5 microns to about 10 microns, including about 7 microns.
In some embodiments, the method of extracting a diatom frustule
portion can include obtaining a washed diatom frustule portion.
Obtaining the washed diatom frustule portion may comprise washing
the plurality of diatom frustule portions with a cleaning solvent
after removing the at least one of the organic contaminant and the
inorganic contaminant. In some embodiments, obtaining the washed
diatom frustule portion can comprise washing the diatom frustule
portion having the at least one common characteristic with a
cleaning solvent.
The cleaning solvent may be removed. For example, removing the
cleaning solvent may comprise sedimenting the plurality of diatom
frustule portions after removing at least one of the organic
contaminant and the inorganic contaminant. For example, removing
the cleaning solvent may comprise sedimenting the plurality of
diatom frustule portions having the at least one common
characteristic. Sedimenting the plurality of diatom frustule
portions may comprise centrifuging. In some embodiments,
centrifuging can comprise applying a centrifuge suitable for large
scale processing. In some embodiments, centrifuging can comprise
applying at least one of a disc stack centrifuge, a decanter
centrifuge, and a tubular bowl centrifuge.
In some embodiments, at least one of the dispersing solvent and the
cleaning solvent can comprise water.
In some embodiments, at least one of dispersing the plurality of
diatom frustule portions in the dispersing solvent and dispersing
the plurality of diatom frustule portions in the surfactant can
comprise sonicating the plurality of diatom frustules.
The surfactant may comprise a cationic surfactant. For example, the
cationic surfactant may comprise at least one of a benzalkonium
chloride, a cetrimonium bromide, a lauryl methyl gluceth-10
hydroxypropyl dimonium chloride, a benzethonium chloride, a
benzethonium chloride, a bronidox, a dimethyldioctadecylammonium
chloride, and a tetramethylammonium hydroxide.
The surfactant may comprise a non-ionic surfactant. For example,
the non-ionic surfactant may comprise at least one of a cetyl
alcohol, a stearyl alcohol, a cetostearyl alcohol, an oleyl
alcohol, a polyoxyethylene glycol alkyl ether, an octaethylene
glycol monododecyl ether, a glucoside alkyl ethers, a decyl
glucoside, a polyoxyethylene glycol octylphenol ethers, an
octylphenol ethoxylate (Triton X-100.TM.), a nonoxynol-9, a
glyceryl laurate, a polysorbate, and a poloxamer.
In some embodiments, the method of extracting a diatom frustule
portion can comprise dispersing the plurality of diatom frustules
in an additive component. Dispersing the plurality of diatom
frustules in an additive component may be before dispersing the
plurality of diatom frustules in the surfactant. Dispersing the
plurality of diatom frustules in an additive component may be after
dispersing the plurality of diatom frustules in the surfactant.
Dispersing the plurality of diatom frustules in an additive
component may be at least partially simultaneous with dispersing
the plurality of diatom frustules in the surfactant. The additive
component may include at least one of a potassium chloride, an
ammonium chloride, an ammonium hydroxide, and a sodium
hydroxide.
In some embodiments, dispersing the plurality of diatom frustule
portions can comprise obtaining a dispersion comprising about 1
weight percent to about 5 weight percent of the plurality of diatom
frustule portions.
In some embodiments, removing the organic contaminant can comprise
heating the plurality of diatom frustule portions in the presence
of a bleach. The bleach may include at least one of a hydrogen
peroxide and a nitric acid. Heating the plurality of diatom
frustule portions may comprise heating the plurality of diatom
frustule portions in a solution comprising an amount of hydrogen
peroxide in a range from about 10 volume percent to about 20 volume
percent. Heating the plurality of diatom frustule portions may
comprise heating the plurality of diatom frustule portions for a
duration of about 5 minutes to about 15 minutes.
In some embodiments, removing the organic contaminant can comprise
annealing the plurality of diatom frustule portions. In some
embodiments, removing the inorganic contaminant can comprise
combining the plurality of diatom frustule portions with at least
one of a hydrochloric acid and a sulfuric acid. Combining the
plurality of diatom frustule portions with at least one of a
hydrochloric acid and a sulfuric acid may include mixing the
plurality of diatom frustule portions in a solution comprising
about 15 volume percent to about 25 volume percent of hydrochloric
acid. For example, the mixing may be for a duration of about 20
minutes to about 40 minutes.
A method of forming silver nanostructures on a diatom frustule
portion may include forming a silver seed layer on a surface of the
diatom frustule portion. The method may include forming a
nanostructure on the seed layer.
In some embodiments, the nanostructures can comprise at least one
of a coating, a nanowire, a nanoplate, a dense array of
nanoparticles, a nanobelt, and a nanodisk. In some embodiments, the
nanostructures can comprise silver.
Forming the silver seed layer may comprise applying a cyclic
heating regimen to a first silver contributing component and the
diatom frustule portion. In some embodiments, applying the cyclic
heating regimen can comprise applying a cyclic microwave power.
Applying the cyclic microwave power may comprise alternating a
microwave power between about 100 Watt and 500 Watt. For example,
alternating may comprise alternating the microwave power every
minute. In some embodiments, alternating can comprise alternating
the microwave power for a duration of about 30 minutes. In some
embodiments, alternating can comprise alternating the microwave
power for a duration of about 20 minutes to about 40 minutes.
In some embodiments, forming the silver seed layer can comprise
combining the diatom frustule portion with a seed layer solution.
The seed layer solution may include the first silver contributing
component and a seed layer reducing agent. For example, the seed
layer reducing agent may be a seed layer solvent. In some
embodiments, the seed layer reducing agent and the seed layer
solvent can comprise a polyethylene glycol.
In some embodiments, the seed layer solution can comprise the first
silver contributing component, a seed layer reducing agent and a
seed layer solvent.
Forming the silver seed layer may comprise mixing the diatom
frustule portion with the seed layer solution. In some embodiments,
the mixing can comprise ultrasonicating.
In some embodiments, the seed layer reducing agent can comprise a
N,N-Dimethylformamide, the first silver contributing component can
comprise a silver nitrate, and the seed layer solvent can comprise
at least one of a water and a polyvinylpyrrolidone.
Forming the nanostructure may comprise combining the diatom
frustule portion with a nanostructure forming reducing agent. In
some embodiments, forming the nanostructure further may include
heating the diatom frustule portion after combining the diatom
frustule portion with the nanostructure forming reducing agent. For
example, the heating may comprise heating to a temperature of about
120.degree. C. to about 160.degree. C.
In some embodiments, forming the nanostructure can include
titrating the diatom frustule portion with a titration solution
comprising a nanostructure forming solvent and a second silver
contributing component. In some embodiments, forming the
nanostructure can comprise mixing after titrating the diatom
frustule portion with the titration solution.
In some embodiments, at least one of the seed layer reducing agent
and the nanostructure forming reducing agent can comprise at least
one of a hydrazine, a formaldehyde, a glucose, sodium tartrate, an
oxalic acid, a formic acid, an ascorbic acid, and an ethylene
glycol.
In some embodiments, at least one of the first silver contributing
component and the second silver contributing component can comprise
at least one of a silver salt and a silver oxide. For example, the
silver salt may include at least one of a silver nitrate and an
ammoniacal silver nitrate, a silver chloride (AgCl), a silver
cyanide (AgCN), a silver tetrafluoroborate, a silver
hexafluorophosphate, and a silver ethylsulphate.
Forming the nanostructure may be in an ambient to reduce oxide
formation. For example, the ambient may comprise an argon
atmosphere.
In some embodiments, at least one of the seed layer solvent and the
nanostructure forming solvent can comprise at least one of a
propylene glycol, a water, a methanol, an ethanol, a 1-propanol, a
2-propanol a 1-methoxy-2-propanol, a 1-butanol, a 2-butanol a
1-pentanol, a 2-pentanol, a 3-pentanol, a 1-hexanol, a 2-hexanol, a
3-hexanol, an octanol, a 1-octanol, a 2-octanol, a 3-octanol, a
tetrahydrofurfuryl alcohol (THFA), a cyclohexanol, a cyclopentanol,
a terpineol, a butyl lactone; a methyl ethyl ether, a diethyl
ether, an ethyl propyl ether, a polyethers, a diketones, a
cyclohexanone, a cyclopentanone, a cycloheptanone, a cyclooctanone,
an acetone, a benzophenone, an acetylacetone, an acetophenone, a
cyclopropanone, an isophorone, a methyl ethyl ketone, an ethyl
acetate, a dimethyl adipate, a propylene glycol monomethyl ether
acetate, a dimethyl glutarate, a dimethyl succinate, a glycerin
acetate, a carboxylates, a propylene carbonate, a glycerin, a diol,
a triol, a tetraol, a pentanol, an ethylene glycol, a diethylene
glycol, a polyethylene glycol, a propylene glycol, a dipropylene
glycol, a glycol ether, a glycol ether acetate, a 1,4-butanediol, a
1,2-butanediol, a 2,3-butanediol, a 1,3-propanediol, a
1,4-butanediol, a 1,5-pentanediol, a 1,8-octanediol, a
1,2-propanediol, a 1,3-butanediol, a 1,2-pentanediol, an
etohexadiol, a p-menthane-3,8-diol, a 2-methyl-2,4-pentanediol, a
tetramethyl urea, a n-methylpyrrolidone, an acetonitrile, a
tetrahydrofuran (THF), a dimethyl formamide (DMF), a N-methyl
formamide (NMF), a dimethyl sulfoxide (DMSO), a thionyl chloride
and a sulfuryl chloride.
The diatom frustule portion may comprise a broken diatom frustule
portion. The diatom frustule portion may comprise an unbroken
diatom frustule portion. In some embodiments, the diatom frustule
portion can be obtained through a diatom frustule portion
separation process. For example, the process may comprise at least
one of using a surfactant to reduce an agglomeration of a plurality
of diatom frustule portions and using a disc stack centrifuge.
A method of forming zinc-oxide nanostructures on a diatom frustule
portion may include forming a zinc-oxide seed layer on a surface of
the diatom frustule portion. The method may comprise forming a
nanostructure on the zinc-oxide seed layer.
In some embodiments, the nanostructure can comprise at least one of
a nanowire, a nanoplate, a dense array of nanoparticles, a
nanobelt, and a nanodisk. In some embodiments, the nanostructures
can comprise zinc-oxide.
Forming the zinc-oxide seed layer may comprise heating a first zinc
contributing component and the diatom frustule portion. In some
embodiments, heating the first zinc contributing component and the
diatom frustule portion can comprise heating to a temperature in a
range from about 175.degree. C. to about 225.degree. C.
In some embodiments, forming the nanostructure can comprise
applying a heating regimen to the diatom frustule portion having
the zinc-oxide seed layer in the presence of a nanostructure
forming solution comprising a second zinc contributing component.
The heating regimen may comprise heating to a nanostructure forming
temperature. For example, the nanostructure forming temperature may
be from about 80.degree. C. to about 100.degree. C. In some
embodiments, the heating may be for a duration of about one to
about three hours. In some embodiments, the heating regimen can
comprise applying a cyclic heating routine. For example, the cyclic
heating routine may include applying a microwave heating to the
diatom frustule portion having the zinc-oxide seed layer for a
heating duration and then turning the microwaving heating off for a
cooling duration, for a total cyclic heating duration. In some
embodiments, the heating duration can be about 1 minute to about 5
minutes. In some embodiments, the cooling duration can be about 30
seconds to about 5 minutes. The total cyclic heating duration may
be about 5 minutes to about 20 minutes. Applying the microwave
heating may include applying about 480 Watt to about 520 Watt of
microwave power, including about 80 Watt to about 120 Watt of
microwave power.
In some embodiments, at least one of the first zinc contributing
component and the second zinc contributing component can comprise
at least one of a zinc acetate, a zinc acetate hydrate, a zinc
nitrate, a zinc nitrate hexahydrate, a zinc chloride, a zinc
sulfate, and a sodium zincate.
In some embodiments, the nanostructure forming solution may include
a base. For example, the base may comprise at least one of a sodium
hydroxide, an ammonium hydroxide, potassium hydroxide, a
tetramethylammonium hydroxide, a lithium hydroxide, a
hexamethylenetetramine, an ammonia solution, a sodium carbonate,
and a ethylenediamine.
In some embodiments, forming the nanostructure can comprise adding
an additive component. The additive component may include at least
one of a tributylamine, a triethylamine, a triethanolamine, a
diisopropylamine, an ammonium phosphate, a 1,6-hexadianol, a
triethyldiethylnol, an isopropylamine, a cyclohexylamine, a
n-butylamine, an ammonium chloride, a hexamethylenetetramine, an
ethylene glycol, an ethanolamine, a polyvinylalcohol, a
polyethylene glycol, a sodium dodecyl sulphate, a cetyltrimethyl
ammonium bromide, and a carbamide.
In some embodiments, at least one of the nanostructure forming
solution and a zinc-oxide seed layer forming solution can comprise
a solvent, the solvent comprising at least one of a propylene
glycol, a water, a methanol, an ethanol, a 1-propanol, a 2-propanol
a 1-methoxy-2-propanol, a 1-butanol, a 2-butanol a 1-pentanol, a
2-pentanol, a 3-pentanol, a 1-hexanol, a 2-hexanol, a 3-hexanol, an
octanol, a 1-octanol, a 2-octanol, a 3-octanol, a
tetrahydrofurfuryl alcohol (THFA), a cyclohexanol, a cyclopentanol,
a terpineol, a butyl lactone; a methyl ethyl ether, a diethyl
ether, an ethyl propyl ether, a polyethers, a diketones, a
cyclohexanone, a cyclopentanone, a cycloheptanone, a cyclooctanone,
an acetone, a benzophenone, an acetylacetone, an acetophenone, a
cyclopropanone, an isophorone, a methyl ethyl ketone, an ethyl
acetate, a dimethyl adipate, a propylene glycol monomethyl ether
acetate, a dimethyl glutarate, a dimethyl succinate, a glycerin
acetate, a carboxylates, a propylene carbonate, a glycerin, a diol,
a triol, a tetraol, a pentanol, an ethylene glycol, a diethylene
glycol, a polyethylene glycol, a propylene glycol, a dipropylene
glycol, a glycol ether, a glycol ether acetate, a 1,4-butanediol, a
1,2-butanediol, a 2,3-butanediol, a 1,3-propanediol, a
1,4-butanediol, a 1,5-pentanediol, a 1,8-octanediol, a
1,2-propanediol, a 1,3-butanediol, a 1,2-pentanediol, an
etohexadiol, a p-menthane-3,8-diol, a 2-methyl-2,4-pentanediol, a
tetramethyl urea, a n-methylpyrrolidone, an acetonitrile, a
tetrahydrofuran (THF), a dimethyl formamide (DMF), a N-methyl
formamide (NMF), a dimethyl sulfoxide (DMSO), a thionyl chloride
and a sulfuryl chloride.
The diatom frustule portion may comprise a broken diatom frustule
portion. The diatom frustule portion may comprise an unbroken
diatom frustule portion. In some embodiments, the diatom frustule
portion can be obtained through a diatom frustule portion
separation process. For example, the process may comprise at least
one of using a surfactant to reduce an agglomeration of a plurality
of diatom frustule portions and using a disc stack centrifuge.
A method of forming carbon nanostructures on a diatom frustule
portion may include forming a metal seed layer on a surface of the
diatom frustule portion. The method may include forming a carbon
nanostructure on the seed layer.
In some embodiments, the carbon nanostructure can comprise a carbon
nanotube. The carbon nanotube may comprise at least one of a
single-walled carbon nanotube and a multi-walled carbon
nanotube.
In some embodiments, forming the metal seed layer can comprise
spray coating the surface of the diatom frustule portion. In some
embodiments, forming the metal seed layer can comprise introducing
the surface of the diatom frustule portion to at least one of a
liquid comprising the metal, a gas comprising the metal and the
solid comprising a metal.
In some embodiments, forming the carbon nanostructure can comprise
using chemical vapor deposition (CVD). Forming the carbon
nanostructure can comprise exposing the diatom frustule portion to
a nanostructure forming reducing gas after exposing the diatom
frustule portion to a nanostructure forming carbon gas. Forming the
carbon nanostructure may comprise exposing the diatom frustule
portion to a nanostructure forming reducing gas before exposing the
diatom frustule portion to a nanostructure forming carbon gas. In
some embodiments, forming the carbon nanostructure comprises
exposing the diatom frustule portion to a nanostructure forming gas
mixture comprising a nanostructure forming reducing gas and a
nanostructure forming carbon gas. The nanostructure forming gas
mixture may include a neutral gas. For example, the neutral gas may
be argon.
In some embodiments, the metal can comprise at least one of a
nickel, an iron, a cobalt, a cobalt-molybdenum bimetallic, a
copper, a gold, a silver, a platinum, a palladium, a manganese, an
aluminum, a magnesium, a chromium, an antimony, an
aluminum-iron-molybdenum (Al/Fe/Mo), an iron pentacarbonyl
(Fe(CO).sub.5), an iron (III) nitrate hexahydrate
((Fe(NO.sub.3).sub.3.6H.sub.2O), a cobalt (II) chloride hexahydrate
(CoCl.sub.2.6H.sub.2O), an ammonium molybdate tetrahydrate
((NH.sub.4).sub.6Mo.sub.7O.sub.24.4H.sub.2O), a molybdenum (VI)
dichloride dioxide MoO.sub.2Cl.sub.2, and an alumina
nanopowder.
In some embodiments, the nanostructure forming reducing gas can
comprise at least one of an ammonia, a nitrogen, and a hydrogen.
The nanostructure forming carbon gas may comprise at least one of
an acetylene, an ethylene, an ethanol, a methane, a carbon oxide,
and a benzene.
In some embodiments, forming the metal seed layer can comprise
forming a silver seed layer. Forming the silver seed layer may
comprise forming a silver nanostructure on the surface of the
diatom frustule portion.
The diatom frustule portion may comprise a broken diatom frustule
portion. The diatom frustule portion may comprise an unbroken
diatom frustule portion. In some embodiments, the diatom frustule
portion can be obtained through a diatom frustule portion
separation process. For example, the process may comprise at least
one of using a surfactant to reduce an agglomeration of a plurality
of diatom frustule portions and using a disc stack centrifuge.
A method of fabricating a silver ink may include combining an
ultraviolet light sensitive component and a plurality of diatom
frustule portions having a silver nanostructure on a surface of the
plurality of diatom frustule portions, the surface comprising a
plurality of perforations.
In some embodiments, the method of fabricating the silver ink can
comprise forming a silver seed layer on the surface of the
plurality of diatom frustule portions. In some embodiments, the
method can include forming the silver nanostructure on the seed
layer.
The plurality of diatom frustule portions may include a plurality
of broken diatom frustule portions. The plurality of diatom
frustule portions may include a plurality of diatom frustule
flakes.
In some embodiments, the silver ink is depositable in a layer
having a thickness of about 5 microns to about 15 microns after
curing. In some embodiments, at least one of the plurality of
perforations has a diameter of about 250 nanometers to about 350
nanometers. In some embodiments, the silver nanostructure can
comprise a thickness of about 10 nanometers to about 500
nanometers. The silver ink may comprise an amount of diatom
frustules within a range of about 50 weight percent to about 80
weight percent.
Forming the silver seed layer may include forming the silver seed
layer on a surface within the plurality of perforations to form a
plurality of silver seed plated perforations. Forming the silver
seed layer may include forming the silver seed layer on
substantially all surfaces of the plurality of diatom frustule
portions.
In some embodiments, forming the silver nanostructure may comprise
forming the silver nanostructure on a surface within the plurality
of perforations to form a plurality of silver nanostructure plated
perforations. Forming the silver nanostructure may comprise forming
the silver nanostructure on substantially all surfaces of the
plurality of diatom frustule portions.
In some embodiments, the ultraviolet light sensitive component can
be sensitive to an optical radiation having a wavelength shorter
than a dimension of the plurality of perforations. The ultraviolet
light sensitive component may be sensitive to an optical radiation
having a wavelength shorter than a dimension of at least one of the
plurality of silver seed plated perforations and the plurality of
silver nanostructure plated perforations.
In some embodiments, combining the plurality of diatom frustule
portions with the ultraviolet light sensitive component can include
combining the plurality of diatom frustule portions with a
photoinitiation synergist agent. For example, the photoinitiation
synergist agent may comprise at least one of an ethoxylated
hexanediol acrylate, a propoxylated hexanediol acrylate, an
ethoxylated trimethylpropane triacrylate, a triallyl cyanurate and
an acrylated amine.
In some embodiments, combining the plurality of diatom frustule
portions with the ultraviolet light sensitive component can include
combining the plurality of diatom frustule portions with a
photoinitiator agent. The photoinitiator agent may include at least
one of a 2-methyl-1-(4-methylthio)phenyl-2-morpholinyl-1-propanone
and an isopropyl thioxanthone.
In some embodiments, combining the plurality of diatom frustule
portions with the ultraviolet light sensitive component can include
combining the plurality of diatom frustule portions with a polar
vinyl monomer. For example, the polar vinyl monomer may include at
least one of a n-vinyl-pyrrolidone and a n-vinylcaprolactam.
The method of fabricating the silver ink may comprise combining the
plurality of diatom frustule portions with a rheology modifying
agent. In some embodiments, the method of fabricating the silver
ink can comprise combining the plurality of diatom frustule
portions with a crosslinking agent. In some embodiments, the method
can include combining the plurality of diatom frustule portions
with a flow and level agent. In some embodiments, the method can
include combining the plurality of diatom frustule portions with at
least one of an adhesion promoting agent, a wetting agent, and a
viscosity reducing agent.
The silver nanostructure may include at least one of a coating, a
nanowire, a nanoplate, a dense array of nanoparticles, a nanobelt,
and a nanodisk.
In some embodiments, forming the silver seed layer can comprise
applying a cyclic heating regimen to a first silver contributing
component and the plurality of diatom frustule portions.
Forming the silver seed layer may comprise combining the diatom
frustule portion with a seed layer solution. For example, the seed
layer solution may comprise the first silver contributing component
and a seed layer reducing agent.
Forming the silver nanostructure may comprise combining the diatom
frustule portion with a nanostructure forming reducing agent. In
some embodiments, forming the silver nanostructure can comprise
heating the diatom frustule portion after combining the diatom
frustule portion with the nanostructure forming reducing agent. In
some embodiments, forming the silver nanostructure can comprise
titrating the diatom frustule portion with a titration solution
comprising a nanostructure forming solvent and a second silver
contributing component.
In some embodiments, the plurality of diatom frustule portions can
be obtained through a diatom frustule portion separation process.
For example, the process may include at least one of using a
surfactant to reduce an agglomeration of a plurality of diatom
frustule portions and using a disc stack centrifuge.
A conductive silver ink may include an ultraviolet light sensitive
component. The conductive ink may include a plurality of diatom
frustule portions having a silver nanostructure on a surface of the
plurality of diatom frustule portions, the surface comprising a
plurality of perforations.
The plurality of diatom frustule portions may include a plurality
of broken diatom frustule portions. The plurality of diatom
frustule portions may include a plurality of diatom frustule
flakes.
In some embodiments, the silver ink is depositable in a layer
having a thickness of about 5 microns to about 15 microns (e.g.,
after curing). In some embodiments, at least one of the plurality
of perforations has a diameter of about 250 nanometers to about 350
nanometers. In some embodiments, the silver nanostructure can
comprise a thickness of about 10 nanometers to about 500
nanometers. The silver ink may comprise an amount of diatom
frustules within a range of about 50 weight percent to about 80
weight percent.
In some embodiments, at least one of the plurality of perforations
can comprise a surface having a silver nanostructure.
In some embodiments, at least one of the plurality of perforations
comprises a surface having a silver seed layer. In some
embodiments, substantially all surfaces of the plurality of diatom
frustule portions can comprise a silver nanostructure.
In some embodiments, the ultraviolet light sensitive component can
be sensitive to an optical radiation having a wavelength shorter
than a dimension of the plurality of perforations.
In some embodiments, the conductive silver ink can be curable by an
ultraviolet radiation. In some embodiments, the plurality of
perforations can have a dimension sufficient to allow the
ultraviolet radiation to pass through. The conductive silver ink
may be depositable in a layer having a thickness of about 5 microns
to about 15 microns (e.g., after curing).
In some embodiments, the conductive silver ink can be thermally
curable.
The ultraviolet light sensitive component may include a
photoinitiation synergist agent. For example, the photoinitiation
synergist agent may comprise at least one of an ethoxylated
hexanediol acrylate, a propoxylated hexanediol acrylate, an
ethoxylated trimethylpropane triacrylate, a triallyl cyanurate and
an acrylated amine.
The ultraviolet light sensitive component may include a
photoinitiator agent. The photoinitiator agent may include at least
one of a 2-methyl-1-(4-methylthio)phenyl-2-morpholinyl-1-propanone
and an isopropyl thioxanthone.
In some embodiments, the ultraviolet light sensitive component can
include a polar vinyl monomer. For example, the polar vinyl monomer
may include at least one of a n-vinyl-pyrrolidone and a
n-vinylcaprolactam.
The conductive silver ink may include at least one of a rheology
modifying agent, a crosslinking agent, a flow and level agent, a
adhesion promoting agent, a wetting agent, and a viscosity reducing
agent. In some embodiments, the silver nanostructure can comprise
at least one of a coating, a nanowire, a nanoplate, a dense array
of nanoparticles, a nanobelt, and a nanodisk.
A method of fabricating a silver film may include curing a mixture
comprising an ultraviolet light sensitive component and a plurality
of diatom frustule portions having a silver nanostructure on a
surface of the plurality of diatom frustule portions, the surface
comprising a plurality of perforations.
In some embodiments, the method of fabricating the silver film can
comprise forming a silver seed layer on the surface of the
plurality of diatom frustule portions. In some embodiments, the
method can comprise forming the silver nanostructure on the seed
layer. In some embodiments, the method can include combining the
plurality of diatom frustule portions with the ultraviolet light
sensitive component to form a silver ink.
The plurality of diatom frustule portions may comprise a plurality
of broken diatom frustule portions. The plurality of diatom
frustule portions may comprise a plurality of diatom frustule
flakes.
In some embodiments, the silver ink is depositable in a layer
having a thickness of about 5 microns to about 15 microns (e.g.,
after curing). In some embodiments, at least one of the plurality
of perforations has a diameter of about 250 nanometers to about 350
nanometers. In some embodiments, the silver nanostructure can
comprise a thickness of about 10 nanometers to about 500
nanometers. The silver ink may comprise an amount of diatom
frustules within a range of about 50 weight percent to about 80
weight percent.
Forming the silver seed layer may comprise forming the silver seed
layer on a surface within the plurality of perforations to form a
plurality of silver seed plated perforations. Forming the silver
seed layer may comprise forming the silver seed layer on
substantially all surfaces of the plurality of diatom frustule
portions.
Forming the silver nanostructure may comprise forming the silver
nanostructure on a surface within the plurality of perforations to
form a plurality of silver nanostructure plated perforations.
Forming the silver nanostructure may comprise forming the silver
nanostructure on substantially all surfaces of the plurality of
diatom frustule portions.
In some embodiments, curing the mixture can comprise exposing the
mixture to an ultraviolet light having a wavelength shorter than a
dimension of the plurality of perforations. In some embodiments,
curing the mixture can comprise exposing the mixture to an
ultraviolet light having a wavelength shorter than a dimension of
at least one of the plurality of silver seed plated perforations
and the plurality of silver nanostructure plated perforations.
In some embodiments, curing the mixture can comprise thermally
curing the mixture.
The ultraviolet light sensitive component may be sensitive to an
optical radiation having a wavelength shorter than a dimension of
the plurality of perforations. In some embodiments, the ultraviolet
light sensitive component can be sensitive to an optical radiation
having a wavelength shorter than a dimension of at least one of the
plurality of silver seed plated perforations and the plurality of
silver nanostructure plated perforations.
Combining the plurality of diatom frustule portions with the
ultraviolet light sensitive component may comprise combining the
plurality of diatom frustule portions with a photoinitiation
synergist agent. For example, the photoinitiation synergist agent
may include at least one of an ethoxylated hexanediol acrylate, a
propoxylated hexanediol acrylate, an ethoxylated trimethylpropane
triacrylate, a triallyl cyanurate and an acrylated amine.
In some embodiments, combining the plurality of diatom frustule
portions with the ultraviolet light sensitive component can
comprise combining the plurality of diatom frustule portions with a
photoinitiator agent. The photoinitiator agent may include at least
one of a 2-methyl-1-(4-methylthio)phenyl-2-morpholinyl-1-propanone
and an isopropyl thioxanthone.
In some embodiments, combining the plurality of diatom frustule
portions with the ultraviolet light sensitive component can
comprise combining the plurality of diatom frustule portions with a
polar vinyl monomer. The polar vinyl monomer may include at least
one of a n-vinyl-pyrrolidone and a n-vinylcaprolactam.
The method of fabricating the conductive silver ink may include
combining the plurality of diatom frustule portions with a rheology
modifying agent. In some embodiments, the method of fabricating the
conductive silver ink can include combining the plurality of diatom
frustule portions with a crosslinking agent. In some embodiments,
the method can comprise combining the plurality of diatom frustule
portions with a flow and level agent. The method may include
combining the plurality of diatom frustule portions with at least
one of an adhesion promoting agent, a wetting agent, and a
viscosity reducing agent.
In some embodiments, the silver nanostructure can comprise at least
one of a coating, a nanowire, a nanoplate, a dense array of
nanoparticles, a nanobelt, and a nanodisk.
In some embodiments, forming the silver seed layer can comprise
applying a cyclic heating regimen to a first silver contributing
component and the plurality of diatom frustule portions.
Forming the silver seed layer may comprise combining the diatom
frustule portion with a seed layer solution. For example, the seed
layer solution may comprise the first silver contributing component
and a seed layer reducing agent.
Forming the silver nanostructure may comprise combining the diatom
frustule portion with a nanostructure forming reducing agent. In
some embodiments, forming the silver nanostructure can comprise
heating the diatom frustule portion after combining the diatom
frustule portion with the nanostructure forming reducing agent. In
some embodiments, forming the silver nanostructure can comprise
titrating the diatom frustule portion with a titration solution
comprising a nanostructure forming solvent and a second silver
contributing component.
In some embodiments, the plurality of diatom frustule portions can
be obtained through a diatom frustule portion separation process.
For example, the process may include at least one of using a
surfactant to reduce an agglomeration of a plurality of diatom
frustule portions and using a disc stack centrifuge.
A conductive silver film may include a plurality of diatom frustule
portions having a silver nanostructure on a surface of each of the
plurality of diatom frustule portions, the surface comprising a
plurality of perforations.
In some embodiments, the plurality of diatom frustule portions can
comprise a plurality of broken diatom frustule portion. The
plurality of diatom frustule portions may include a plurality of
diatom frustule flakes.
In some embodiments, at least one of the plurality of perforations
has a diameter of about 250 nanometers to about 350 nanometers. In
some embodiments, the silver nanostructure can comprise a thickness
of about 10 nanometers to about 500 nanometers.
In some embodiments, at least one of the plurality of perforations
can comprise a surface having a silver nanostructure. In some
embodiments, at least one of the plurality of perforations can
comprise a surface having a silver seed layer. Substantially all
surfaces of the plurality of diatom frustule portions may comprise
a silver nanostructure.
In some embodiments, the silver nanostructure can comprise at least
one of a coating, a nanowire, a nanoplate, a dense array of
nanoparticles, a nanobelt, and a nanodisk.
In some embodiments, the conductive silver film can comprise a
binder resin.
A printed energy storage device can include a first electrode, a
second electrode, and a separator between the first electrode and
the second electrode, where at least one of the first electrode and
the second electrode can include a plurality of frustules having
manganese-containing nanostructures.
In some embodiments, the frustules have a substantially uniform
property, the substantially uniform property including at least one
of a frustule shape, a frustule dimension, a frustule porosity, a
frustule mechanical strength, a frustule material, and a degree of
brokenness of a frustule.
In some embodiments, the manganese-containing nanostructures can
include an oxide of manganese. The oxide of manganese may include
manganese(II,III) oxide. The oxide of manganese may include
manganese oxyhydroxide.
In some embodiments, at least one of the first electrode and the
second electrode can include frustules having zinc-oxide
nanostructures. The zinc-oxide nanostructures can include at least
one of a nano-wire and a nano-plate.
In some embodiments, the manganese-containing nanostructures cover
substantially all surfaces of the frustules. In some embodiments,
manganese-containing nanostructures cover some surfaces of the
frustules and carbon-containing nanostructures cover other surfaces
of the frustules, the manganese-containing nanostructures
interspersed with the carbon-containing nanostructures.
A membrane of an energy storage device can include frustules having
manganese-containing nanostructures.
In some embodiments, the manganese-containing nanostructures can
include an oxide of manganese. The oxide of manganese may include
manganese(II,III) oxide. The oxide of manganese may include
manganese oxyhydroxide. In some embodiments, manganese-containing
nanostructures cover some surfaces of the frustules and
carbon-containing nanostructures cover other surfaces of the
frustules, the manganese-containing nanostructures interspersed
with the carbon-containing nanostructures.
In some embodiments, at least some of the manganese-containing
nanostructures can be a nano-fiber. In some embodiments, at least
some of the manganese-containing nanostructures have a tetrahedral
shape.
In some embodiments, the energy storage device includes a
zinc-manganese battery.
An ink for a printed film can include a solution, and frustules
having manganese-containing nanostructures dispersed in the
solution.
In some embodiments, the manganese-containing nanostructures can
include an oxide of manganese. In some embodiments, the
manganese-containing nanostructures can include at least one of
MnO.sub.2, MnO, Mn.sub.2O.sub.3, MnOOH, and Mn.sub.3O.sub.4.
In some embodiments, at least some of the manganese-containing
nanostructures can include a nano-fiber. In some embodiments, at
least some of the manganese-containing nanostructures have a
tetrahedral shape.
In some embodiments, manganese-containing nanostructures cover some
surfaces of the frustules and carbon-containing nanostructures
cover other surfaces of the frustules, the manganese-containing
nanostructures interspersed with the carbon-containing nano
structures.
In some embodiments, an energy storage device can include a cathode
having a first plurality of frustules, the first plurality of
frustules having nanostructures including an oxide of manganese;
and an anode having a second plurality of frustules, the second
plurality of frustules having nanostructures including zinc oxide.
In some embodiments, the device can be a rechargeable battery.
In some embodiments, the oxide of manganese includes MnO. In some
embodiments, the oxide of manganese includes at least one of
Mn.sub.3O.sub.4, Mn.sub.2O.sub.3, and MnOOH.
In some embodiments, at least one of the first plurality of
frustules includes a ratio of a mass of the oxide of manganese to a
mass of the at least one frustule of about 1:20 to about 20:1. In
some embodiments, at least one of the second plurality of frustules
includes a ratio of a mass of the zinc oxide to a mass of the at
least one frustule of about 1:20 to about 20:1.
In some embodiments, the anode can include an electrolyte salt. The
electrolyte salt may include a zinc salt.
In some embodiments, at least one of the cathode and the anode can
include carbon nanotubes. In some embodiments, at least one of the
cathode and the anode can include a conductive filler. The
conductive filler may include graphite.
In some embodiments, the energy storage device can have a separator
between the cathode and the anode, where the separator includes a
third plurality of frustules. The third plurality of frustules may
have substantially no surface modifications.
In some embodiments, at least one of the cathode, the anode, and
the separator can include an ionic liquid.
In some embodiments, the first plurality of frustules having a
first plurality of pores substantially not occluded by the
nanostructures including the oxide of manganese, and where the
second plurality of frustules has a second plurality of pores
substantially not occluded by the nanostructures including the zinc
oxide.
In some embodiments, a frustule can include a plurality of
nanostructures on at least one surface, where the plurality of
nanostructures includes zinc oxide, and where a ratio of a mass of
the plurality of nanostructures to a mass of the frustule is about
1:1 to about 20:1. In some embodiments, the plurality of
nanostructures includes at least one of nanowires, nanoplates,
dense nanoparticles, nanobelts, and nanodisks. In some embodiments,
the frustule includes a plurality of pores substantially not
occluded by the plurality of nanostructures.
In some embodiments, a frustule can include a plurality of
nanostructures on at least one surface, where the plurality of
nanostructures includes an oxide of manganese, and where a ratio of
a mass of the plurality of nanostructures to a mass of the frustule
is about 1:1 to about 20:1. In some embodiments, the oxide of
manganese includes MnO. In some embodiments, the oxide of manganese
includes Mn.sub.3O.sub.4. In some embodiments, the oxide of
manganese includes at least one of Mn.sub.2O.sub.3 and MnOOH. In
some embodiments, the plurality of nanostructures includes at least
one of nanowires, nanoplates, dense nanoparticles, nanobelts, and
nanodisks. In some embodiments, the frustule includes a plurality
of pores substantially not occluded by the plurality of
nanostructures.
In some embodiments, an electrode of an energy storage device can
include a plurality of frustules, where each of the plurality of
frustules includes a plurality of nanostructures formed on at least
one surface, where at least one of the plurality of frustules has a
ratio of a mass of the plurality of nanostructures to a mass of the
at least one frustule of about 1:20 to about 20:1.
In some embodiments, the electrode can include carbon nanotubes. In
some embodiments, the electrode can include a conductive filler.
The conductive filler may include graphite. In some embodiments,
the electrode can include an ionic liquid.
In some embodiments, each of the plurality of frustules includes a
plurality of pores substantially not occluded by the plurality of
nanostructures.
The electrode may be an anode of the energy storage device. In some
embodiments, the anode can include an electrolyte salt. In some
embodiments, the electrolyte salt can include a zinc salt. In some
embodiments, the plurality of nanostructures can include zinc
oxide. In some embodiments, the plurality of nanostructures can
include at least one of nanowires, nanoplates, dense nanoparticles,
nanobelts, and nanodisks.
The electrode may be a cathode of the energy storage device. In
some embodiments, the plurality of nanostructures can include an
oxide of manganese. In some embodiments, the oxide of manganese can
include MnO. In some embodiments, the oxide of manganese can
include at least one of Mn.sub.3O.sub.4, Mn.sub.2O.sub.3 and
MnOOH.
In some embodiments, an energy storage device can include a cathode
having a first plurality of frustules, the first plurality of
frustules having nanostructures including an oxide of manganese;
and an anode having a second plurality of frustules, the second
plurality of frustules having nanostructures including zinc oxide.
In some embodiments, the device can be a rechargeable battery. In
some embodiments, at least one of the first plurality of frustules
includes a ratio of a mass of the oxide of manganese to a mass of
the at least one frustule of about 1:20 to about 100:1. In some
embodiments, at least one of the second plurality of frustules
includes a ratio of a mass of the zinc oxide to a mass of the at
least one frustule of about 1:20 to about 100:1.
In some embodiments, a frustule can include a plurality of
nanostructures on at least one surface, where the plurality of
nanostructures includes zinc oxide, and where a ratio of a mass of
the plurality of nanostructures to a mass of the frustule is about
1:1 to about 100:1.
In some embodiments, a frustule can include a plurality of
nanostructures on at least one surface, where the plurality of
nanostructures includes an oxide of manganese, and where a ratio of
a mass of the plurality of nanostructures to a mass of the frustule
is about 1:1 to about 100:1.
In some embodiments, an electrode of an energy storage device can
include a plurality of frustules, where each of the plurality of
frustules includes a plurality of nanostructures formed on at least
one surface, where at least one of the plurality of frustules has a
ratio of a mass of the plurality of nanostructures to a mass of the
at least one frustule of about 1:20 to about 100:1.
In some embodiments, a supercapacitor comprises a pair of
electrodes and an electrolyte comprising an ionic liquid, wherein
at least one of the electrodes comprises a plurality of frustules
having formed thereon a surface active material.
In some embodiments, a supercapacitor comprises a pair of
electrodes contacting an electrolyte, wherein at least one of the
electrodes comprise a plurality of frustules and a zinc oxide.
In some embodiments, supercapacitor comprises a pair of electrodes
contacting a non-aqueous electrolyte, wherein at least one of the
electrodes comprise a plurality of frustules and a manganese
oxide.
In some embodiments, a method of fabricating a supercapacitor
comprises forming a separator between a pair of electrodes, wherein
the separator comprises frustules, an electrolyte and a thermally
conductive additive, wherein the thermally conductive additive is
adapted to substantially absorb a near infrared (NIR) radiation
upon being applied to the separator, thereby causing heating of the
separator to accelerate drying.
For purposes of summarizing the invention and the advantages
achieved over the prior art, certain objects and advantages are
described herein. Of course, it is to be understood that not
necessarily all such objects or advantages need to be achieved in
accordance with any particular embodiment. Thus, for example, those
skilled in the art will recognize that the invention may be
embodied or carried out in a manner that can achieve or optimize
one advantage or a group of advantages without necessarily
achieving other objects or advantages.
All of these embodiments are intended to be within the scope of the
invention herein disclosed. These and other embodiments will become
readily apparent to those skilled in the art from the following
detailed description having reference to the attached figures, the
invention not being limited to any particular disclosed
embodiment(s).
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, aspects, and advantages of the present
disclosure are described with reference to the drawings of certain
embodiments, which are intended to illustrate certain embodiments
and not to limit the invention.
FIG. 1 is a scanning electron microscope (SEM) image of
diatomaceous earth comprising frustules.
FIG. 2 is a SEM image of an example frustule including a porous
surface.
FIG. 3 is a SEM image of example frustules each having a
substantially cylindrical shape.
FIGS. 4A and 4B are a flow diagram of example steps of a frustule
separation process.
FIG. 5A shows an example embodiment of a frustule comprising
structures on both an exterior surface and an interior surface.
FIG. 5B shows a SEM image, at 50 k.times. magnification, of an
example frustule surface seeded with silver.
FIG. 5C shows a SEM image, at 250 k.times. magnification, of a
frustule surface seeded with silver.
FIG. 5D shows a SEM image, at 20 k.times. magnification, of a
frustule surface having silver nanostructures formed thereon.
FIG. 5E shows a SEM image, at 150 k.times. magnification of a
frustule surface having silver nanostructures formed thereon.
FIG. 5F shows a SEM image, at 25 k.times. magnification, of a
diatom frustule flake having a surface coated by silver
nanostructures.
FIG. 5G shows a SEM image, at 100 k.times. magnification, of a
frustule surface seeded with zinc-oxide.
FIG. 5H shows a SEM image, at 100 k.times. magnification, of a
frustule surface seeded with zinc-oxide.
FIG. 5I shows a SEM image, at 50 k.times. magnification, of a
frustule surface having zinc-oxide nanowires formed thereon.
FIG. 5J shows a SEM image, at 25 k.times. magnification, of a
frustule surface having zinc-oxide nanowires formed thereon.
FIG. 5K shows a SEM image, at 10 k.times. magnification, of a
frustule surface having zinc-oxide nanoplates formed thereon.
FIG. 5L shows a SEM image, at 50 k.times. magnification, of a
frustule surface having silver nanostructures formed thereon.
FIG. 5M shows a SEM image, at 10 k.times. magnification, of a
frustule surface having zinc-oxide nanowires formed thereon.
FIG. 5N shows a SEM image, at 100 k.times. magnification, of a
frustule surface having zinc-oxide nanowires formed thereon.
FIG. 5O shows a SEM image, at 500.times. magnification, of a
plurality of frustules having zinc oxide nanostructures formed
thereon.
FIG. 5P shows a SEM image, at 5 k.times. magnification, of a
frustule having zinc oxide nanostructures formed thereon.
FIG. 5Q shows a SEM image, at 20 k.times. magnification, of a
frustule surface having manganese oxide nanostructures formed
thereon.
FIG. 5R shows a SEM image, at 50 k.times. magnification, of a
frustule surface having manganese oxide nanostructures formed
thereon.
FIG. 5S shows a TEM image of manganese oxide nanocrystals formed on
a frustule surface.
FIG. 5T shows an electron diffraction image of a manganese oxide
particle.
FIG. 5U shows a SEM image, at 10 k.times. magnification, of a
frustule surface having manganese-containing nano-fibers formed
thereon.
FIG. 5V shows a SEM image, at 20 k.times. magnification, of a
frustule having manganese oxide nanostructures formed thereon.
FIG. 5W shows a SEM image, at 50 k.times. magnification, of a
cross-section of an example frustule having manganese oxide
nanostructures formed thereon.
FIG. 5X shows a SEM image, at 100 k.times. magnification, of a
frustule surface having manganese oxide nanostructures formed
thereon.
FIG. 6 schematically illustrates an example embodiment of an energy
storage device.
FIGS. 7A through 7E schematically illustrate examples of energy
storage devices during various steps of different fabrication
processes.
FIG. 8 shows an example embodiment of a separator for an energy
storage device incorporating frustules in a separator layer.
FIG. 9 shows an example embodiment of an electrode for an energy
storage device incorporating frustules in an electrode layer.
FIG. 10 shows a graph of a discharge curve of an example energy
storage device.
FIG. 11 shows a graph of the cycling performance of the energy
storage device of FIG. 10.
FIG. 12 shows a graph of an example charge-discharge performance of
an energy storage device.
FIG. 13 shows another graph of a charge-discharge performance of
the energy storage device of FIG. 12.
FIG. 14A illustrates a cross-sectional view of a supercapacitor
having both electrodes configured as a double-layer capacitor.
FIG. 14B illustrates a cross-sectional view of the supercapacitor
of FIG. 14A in operation, where a voltage is applied across the
electrodes.
FIG. 15 illustrates a cross-sectional view of a supercapacitor
comprising an electrode that is configured as a pseudo
capacitor.
FIGS. 16A and 16B illustrate experimental charge/discharge
measurements performed on a supercapacitor having symmetric printed
electrodes, where each of the electrodes having opposite polarities
comprises frustules having formed thereon zinc oxide
(Zn.sub.xO.sub.y) nano structures.
FIGS. 17A-17D illustrate experimental charge/discharge measurements
performed on a supercapacitor having symmetric printed electrodes,
where each of the electrodes having opposite polarities comprises
frustules having formed thereon manganese oxide (MnO.sub.xO.sub.y)
nanostructures.
FIGS. 18A-18E illustrate experimental charge/discharge measurements
performed on a supercapacitor having asymmetric printed electrodes,
where one of the electrodes having opposite polarities comprises
frustules having formed thereon manganese oxide (MnO.sub.xO.sub.y)
nanostructures, while the other of the electrodes comprises
frustules having formed thereon CNT.
FIGS. 19A-19B illustrate experimental charge/discharge measurements
performed on a supercapacitor having symmetric printed electrodes,
where each of the electrodes having opposite polarities comprises
frustules having formed thereon CNT.
DETAILED DESCRIPTION
Although certain embodiments and examples are described below,
those of skill in the art will appreciate that the invention
extends beyond the specifically disclosed embodiments and/or uses
and obvious modifications and equivalents thereof. Thus, it is
intended that the scope of the invention herein disclosed should
not be limited by any particular embodiments described below.
Energy storage devices used to power electronic devices generally
include batteries (e.g., rechargeable batteries), capacitors, and
super-capacitors (e.g., EDLCs, pseudo capacitors and hybrid
supercapacitors). Energy storage devices may comprise an asymmetric
energy storage device, including, for example, a battery-capacitor
hybrid. Energy storage devices can be manufactured using printing
technologies such as screen printing, roll-to-roll printing,
ink-jet printing, etc. Printed energy storage devices can
facilitate reduced energy storage device thickness, enabling
compact energy storage. Printed energy storage devices can enable
increased energy storage density by facilitating, for example,
stacking of the energy storage devices. Increased energy storage
density may facilitate use of printed energy storage devices for
applications having a large power requirement, such as solar energy
storage. Unlike energy storage devices having a rigid outer casing,
printed energy storage devices may be implemented on a flexible
substrate, enabling a flexible energy storage device. A flexible
energy storage device can facilitate fabrication of flexible
electronic devices, such as flexible electronic display media. Due
to reduced thickness and/or flexible structure, printed energy
storage devices may power cosmetic patches, medical diagnostic
products, remote sensor arrays, smartcards, smart packaging, smart
clothing, greeting cards, etc.
Reliability and durability of a printed energy storage device may
be a factor hindering increased adoption of printed batteries.
Printed energy storage devices typically lack a rigid outer casing,
so printed energy storage devices may not stand up well to
compressive pressure or shape deforming manipulation in use or
production. Variation of an energy storage device layer thickness
in response to compressive pressure or shape deforming manipulation
may adversely affect device reliability. For example, some printed
energy storage devices include electrodes spaced by a separator.
Deviations in separator thickness may cause a short between the
electrodes, such as when a separator is compressible and fails to
maintain a separation between the electrodes under compressive
pressure or shape deforming manipulation.
Costs associated with fabricating a printed energy storage device
may also be a factor hampering use of printed energy storage
devices to power a wider range of applications. Reliable
fabrication of energy storage devices using printing technologies
may facilitate cost-effective energy storage device production.
Printing of an energy storage device may enable integrating the
device printing process into the production of electronic devices,
including for example printed electronic devices powered by the
printed energy storage device, possibly enabling further cost
savings. However, inadequate device structural robustness may
hinder device integrity throughout the fabrication process,
decreasing the feasibility of some printing technologies and
impeding cost-effective production of the printed energy storage
devices. Thickness of a printed energy storage device layer may
also impede the use of certain printing technologies in the
fabrication process, for example due to a device layer thickness
that is greater than a film thickness at which the printing
technology can effectively print.
As described herein, frustules may have significant mechanical
strength or resistance to shear stress, for example due to
dimensions, shape, porosity, and/or material. According to some
implementations described herein, an energy storage device includes
one or more components, for example one or more layers or membranes
of a printed energy storage device, comprising frustules. An energy
storage device comprising frustules may have mechanical strength
and/or structural integrity such that the energy storage device is
able to withstand compressive pressure and/or shape deforming
manipulation, which can occur during manufacture or use, without
failure, such that device reliability can increase. An energy
storage device comprising frustules can resist variations in layer
thicknesses, enabling maintenance of uniform or substantially
uniform device layer thicknesses. For example, a separator
comprising frustules may withstand compressive pressure or shape
deforming manipulation to thereby facilitate improved energy
storage device reliability by maintaining a uniform or
substantially uniform separation distance between electrodes to
inhibit or prevent a short in the device.
Increased mechanical strength in energy storage devices comprising
frustules may facilitate reliable fabrication of the energy storage
devices using various printing technologies, thereby enabling
cost-effective device fabrication due to increased yield and/or
integration of the fabrication process with the production process
of applications powered by the devices.
Energy storage devices may be printed using an ink comprising
frustules. For example, one or more membranes of a printed energy
storage device may comprise frustules. One or more membranes of a
printed energy storage device having frustules may be reliably
printed onto a variety of substrates, including but not limited to,
a flexible or inflexible substrate, a textile, a device, a plastic,
any variety of films such as a metallic or semiconductor film, any
variety of paper, combinations thereof, and/or the like. For
example, suitable substrates may include graphite paper, graphene
paper, polyester film (e.g., Mylar), polycarbonate film aluminum
foil, copper foil, stainless steel foil, carbon foam, combinations
thereof, and/or the like. Fabrication of printed energy storage
devices on flexible substrates may allow for flexible printed
energy storage devices that can be used in a wide array of devices
and implementations due to increased reliability of certain such
printed energy storage devices, for example due to increased
robustness as a result of one or more layers comprising
frustules.
Improved mechanical strength in printed energy storage devices
comprising frustules may also enable a reduced printed device layer
thickness. For example, frustules may provide structural support
for an energy storage device layer, enabling thinner layers having
sufficient structural robustness to withstand compressive pressure
or shape deforming manipulation, which can then reduce an overall
device thickness. Decreased thickness of printed energy storage
devices can further facilitate energy storage density of the
printed devices and/or enable wider use of the printed devices.
A printed energy storage device comprising frustules may have
improved device performance, for example improved device
efficiency. Reduced thickness of an energy storage device layer may
enable improved device performance. Performance of an energy
storage device may depend at least in part on the internal
resistance of the energy storage device. For example, performance
of an energy storage device may depend at least in part on a
separation distance between a first and a second electrode. A
decreased separator membrane thickness for a given measure of
reliability reduces a distance between a first and a second
electrode, which can reduce the internal resistance and improve an
efficiency of the energy storage device. Internal resistance of an
energy storage device may also depend at least in part on the
mobility of ionic species between a first and a second electrode.
Porosity of frustule surfaces may enable mobility of ionic species.
For example, a separator comprising frustules may enable a more
structurally robust separation between electrodes of an energy
storage device while facilitating mobility of ionic species between
the electrodes. Frustule surface porosity may facilitate a direct
path for mobile ionic species between a first electrode and a
second electrode, reducing a resistance and/or increasing
efficiency. Reduced thickness of an electrode layer comprising
frustules and porosity of the electrode frustules may also enable
improved storage device performance. A reduced electrode thickness
may provide increased access of ionic species to active materials
within the electrode. Porosity and/or conductivity of frustules in
an electrode may facilitate mobility of the ionic species within
the electrode. Frustules in an electrode may also enable improved
device performance by, for example, serving as a substrate on which
active materials and/or structures comprising active materials may
be applied or formed, enabling increased surface area for active
materials and thereby facilitating access of ionic species to the
active materials.
FIG. 1 is a SEM image of diatomaceous earth comprising frustules
10.
The frustules 10 have a generally cylindrical shape, although some
frustules are broken or differently shaped. In some embodiments,
the cylindrical frustules 10 have a diameter between about 3 .mu.m
and about 5 .mu.m. In some embodiments, the cylindrical frustules
10 have a length between about 10 .mu.m and about 20 .mu.m. Other
diameters and/or lengths are also possible. The frustules 10 may
have significant mechanical strength or resistance to shear stress,
for example due to architecture (e.g., dimensions, shape),
material, combinations thereof, and/or the like. For example,
mechanical strength of a frustule 10 may be inversely related to
the size of the frustule 10. In some embodiments, a frustule 10
having a longest axis in a range of from about 30 .mu.m to about
130 .mu.m can withstand compressive forces from about 90 .mu.N to
about 730 PT.
FIG. 2 is a SEM image of an example frustule 10 including a porous
surface 12. The porous surface 12 includes circular or
substantially circular openings 14. Other shapes of the openings 14
are also possible (e.g., curved, polygonal, elongate, etc.). In
some embodiments, the porous surface 12 of a frustule 10 has a
uniform or substantially uniform porosity, for example including
openings 14 having uniform or substantially uniform shape,
dimensions, and/or spacing (e.g., as shown in FIG. 2). In some
embodiments, the porous surface 12 of a frustule 10 has a varying
porosity, for example including openings 14 having different
shapes, dimensions, and/or spacing. The porous surfaces 12 of a
plurality of frustules 10 can have uniform or substantially uniform
porosities, or porosity of the porous surfaces 12 of different
frustules 10 may vary. A porous surface 12 may comprise
nanoporosity, including for example microporosity, mesoporosity,
and/or macroporosity.
FIG. 3 is a SEM image of example frustules 10 each having a
cylindrical or substantially cylindrical shape. Frustule features
may differ among different species of diatoms, each diatom species
having frustules of a different shape, size, porosity, material,
and/or another frustule attribute. Diatomaceous earth, which may be
commercially available (e.g., from Mount Sylvia Diatomite Pty Ltd
of Canberra, Australia, Continental Chemical USA of Fort
Lauderdale, Fla., Lintech International LLC of Macon, Ga., etc.),
can serve as a source of frustules. In some embodiments,
diatomaceous earth is sorted according to a pre-determined frustule
feature. For example, sorting may result in frustules each
including a predetermined feature, such as shape, dimensions,
material, porosity, combinations thereof, and/or the like. Sorting
frustules may include one or a variety of separation processes such
as, for example, filtering, screening (e.g., use of vibrating
sieves for separation according to a frustule shape or size), a
separation process involving voraxial or centrifugal technology
(e.g., for separation according to frustule density), any other
suitable solid-solid separation processes, combinations thereof,
and/or the like. Frustules may also be available (e.g., from a
commercial source) already sorted according to a frustule feature
such that the frustules already comprise a uniform or substantially
uniform shape, size, material, porosity, another pre-determined
frustule attribute, combinations thereof, and/or the like. For
example, frustules available from a geographic region (e.g., a
region of a country such as the United States, Peru, Australia,
etc.; a region of the globe; etc.) and/or a type of natural
environment (e.g., freshwater environment, saltwater environment,
etc.) may comprise frustules of a species typically found in that
geographic region and/or environment, providing frustules having a
uniform or substantially uniform shape, size, material, porosity,
another pre-determined frustule attribute, combinations thereof,
and/or the like.
In some embodiments, a separation process can be used to sort
frustules such that only or substantially only unbroken frustules
are retained. In some embodiments, the separation process can be
used to remove broken or small frustules, resulting in only or
substantially only cylindrically-shaped frustules 10 having certain
lengths and/or diameters (e.g., as illustrated in FIG. 3). The
separation process to remove broken frustules may include
screening, such as with the use of a sieve having a mesh size
selected to retain only or substantially only frustules having a
pre-determined dimension. For example, the mesh size of the sieve
may be selected to remove frustules having a dimension (e.g., a
length or diameter) of no more than about 40 .mu.m, no more than
about 30 .mu.m, no more than about 20 .mu.m or no more than about
10 .mu.m, and including ranges bordering and including the
foregoing values. Other sieve mesh sizes may also be suitable.
In some embodiments, the separation process to remove broken
frustules includes application of ultrasonic waves to frustules
placed in a fluid dispersion, including for example ultrasonication
during which frustules dispersed in a water bath are subjected to
ultrasonic waves. Sonication parameters such as power, frequency,
duration, and/or the like may be adjusted based at least in part on
one or more attributes of the frustules. In some embodiments,
ultrasonication includes use of sound waves having a frequency
between about 20 kilohertz (kHz) and about 100 kHz, between about
30 kHz and about 80 kHz, and between about 40 kHz and about 60 kHz.
In some embodiments, ultrasonication may use sound waves having a
frequency of about 20 kHz, about 25 kHz, about 30 kHz, about 35
kHz, about 40 kHz, about 45 kHz, and ranges bordering and including
the foregoing values. The ultrasonication step may have a duration
between about 2 minutes and about 20 minutes, between about 2
minutes and about 15 minutes, and between about 5 minutes and about
10 minutes. In some embodiments, ultrasonication step may have a
duration of about 2 minutes, about 5 minutes, about 10 minutes, and
ranges bordering and including the foregoing values. For example, a
frustule-fluid sample may be subjected to ultrasonic waves at a
frequency of about 35 kHz for a duration of about 5 minutes.
In some embodiments, separation process includes sedimentation. For
example, the separation process may include both ultrasonication
and sedimentation such that heavier particles from the
frustule-fluid sample may be allowed to settle out from the
suspended phase of the frustule-fluid sample during
ultrasonication. In some embodiments, the sedimentation process of
heavier particles from the frustule-fluid sample has a duration
between about 15 seconds and about 120 seconds, between about 20
seconds and about 80 seconds, and between about 30 seconds and
about 60 seconds. In some embodiments, sedimentation has a duration
of no more than about 120 seconds, no more than about 60 seconds,
no more than about 45 seconds, no more than or about 30
seconds.
The separation process to remove broken frustules may include use
of high-velocity centrifugal technology for physical separation
based on density, including for example an ultracentrifugation
step. For example, the separation process may include
ultracentrifugation of the suspended phase of a frustule-fluid
sample. Ultracentrifugation parameters such as angular velocity,
duration, and/or the like may depend at least in part on the
composition of the suspended phase (e.g., a density of the
frustules) and/or characteristics of the equipment used. For
example, the suspended phase may be ultracentrifuged at an angular
velocity between about 10,000 rotations per minute (RPM) and about
40,000 RPM, between about 10,000 RPM and about 30,000 RPM, between
about 10,000 RPM and about 20,000 RPM, and between about 10,000 RPM
and about 15,000 RPM. The suspended phase may be ultracentrifuged
for a duration between about 1 minute and about 5 minutes, between
about 1 minute and about 3 minutes, and between about 1 minute and
about 2 minutes. For example, the suspended phase of the
frustule-fluid sample may be ultracentrifuged at an angular
velocity of about 13,000 RPM for about 1 minute.
FIGS. 4A and 4B are a flow diagram of example steps of a frustule
separation process 20. The process 20 may enable separation of
broken and/or unbroken diatom frustules from a solid mixture
comprising, for example, broken and unbroken diatom frustules. In
some embodiments, the separation process 20 enables large scale
frustule sorting.
As described herein, there can be two sources of diatom frustules
for nanostructured materials and/or nanodevices: living diatoms and
diatomaceous earth. Diatoms can be taken directly from nature or
cultured. Artificially, a large number of identical silica
frustules can be cultured within a few days. To use natural diatoms
for nanostructured materials and/or nanodevices, a separation
process can be performed to separate the diatoms from other organic
materials and/or substances. Another approach is to use
diatomaceous earth. The sediments are abundant and the material is
of low cost.
Diatomaceous earth can have frustules ranging from mixtures of
different diatom species to a single diatom species (e.g.,
including some freshwater sediments). Diatomaceous earth can
comprise broken and/or whole diatom frustules plus contaminating
materials of different origin. Depending on application, one may
use only whole diatom frustules, only broken frustules, or a
mixture of both. For example, when separating whole frustules,
diatomaceous earth with one kind of frustules may be used.
In some embodiments, a method of separating comprises separating
whole diatom frustules from broken pieces of diatom frustules. In
some embodiments, the separation process comprises sorting whole
diatom frustules according to a common frustule characteristic
(e.g., a dimension including a length or diameter, a shape, and/or
a material) and/or sorting portions of diatom frustules based on a
common frustule characteristic (e.g., a dimension including a
length or diameter, a shape, degree of brokenness, and/or a
material). For example, the separation process may enable
extracting a plurality of diatom frustules or portions of diatom
frustules having at least one common characteristic. In some
embodiments, the separation process comprises removing
contaminative material having a different chemical origin from the
diatom frustules and/or portions of diatom frustules.
Diatoms and diatom frustules that stay unchanged during long time
periods are sometimes used in biological, ecological, and related
earth science research. Many approaches have been developed to
extract small samples of frustules from water or sediments. The
sediments (diatomaceous earth) contain diatom frustules (broken and
unbroken) alongside with carbonates, mica, clay, organics and other
sedimentary particles. The separation of unbroken frustules may
involve three main steps: removal of organic remains, removal of
particles with different chemical origin, and removal of broken
pieces. The removal of organic matter may be realized with heating
of samples in a bleach (e.g., hydrogen peroxide and/or nitric
acid), and/or annealing at higher temperatures. The carbonates,
clay, and other soluble non-silica materials may be removed by
hydrochloric and/or sulfuric acid. For the separation of broken and
unbroken frustules, several techniques can be applied: sieving,
sedimentation and centrifugation, centrifugation with a heavy
liquid, and split-flow lateral-transport thin separation cells, and
combinations thereof. A problem for all of these approaches may
often be aggregation of broken and unbroken frustules, which can
diminish the quality of the separation, and/or may render the
separation process suitable only for laboratory size samples.
Scaling up separation procedures may enable diatom frustules to be
used as industrial nanomaterials.
In some embodiments, a separation procedure that can be utilized
for industrial scale separation of diatoms comprises separation of
diatom frustule portions having at least one common characteristic.
For example, the common characteristic could be unbroken diatom
frustules or broken diatom frustules. The separation process 20, as
shown in FIGS. 4A and 4B, is an example separation procedure
enabling industrial scale separation of diatoms. In some
embodiments, a separation procedure that enables large scale
separation of diatoms enables a reduction in the agglomeration of
frustules, such as by using a surfactant and/or a disc stack
centrifuge. In some embodiments, use of the surfactant can enable
the large scale separation. In some embodiments, using the disc
stack centrifuge (e.g., a milk separator type centrifugation
process) can enable large scale separation. For example, use of the
surfactant to disperse diatom frustules together with a disc stack
centrifuge to sort frustules based on a frustule characteristic may
facilitate large scale separation of diatoms by enabling reduced
agglomeration of the diatom frustules. A traditional, non-disk
stack centrifuge process would cause sedimentation of the
frustules. The supernatant fluid would be discarded, and the
sedimented frustules would be redispersed in a solvent, after which
the centrifuge would again cause sedimentation of the frustules.
This process would be repeated until the desired separation is
achieved. A disk stack centrifuge process can continuously
redisperse and separate sedimented frustules. For example, a phase
enriched with whole diatoms can be continuously circulated through
the disk stack centrifuge, becoming more and more enriched. In some
embodiments, the disc stack centrifuge can enable a separation of
broken diatom frustules from unbroken diatom frustules. In some
embodiments, the disc stack centrifuge can enable a sorting of the
diatom frustules according to a diatom frustule characteristic. For
example, the disc stack centrifuge may enable extraction of
frustules having at least one common characteristic (e.g., a
dimension, a shape, a degree of brokenness and/or a material).
A separation procedure enabling industrial scale separation of
diatoms, such as the separation process 20 shown in FIGS. 4A and
4B, may include the following steps:
1. Particles of a solid mixture (e.g., diatomaceous earth)
comprising the diatom frustules and/or portions of diatom frustules
may be rocky and can be broken down into smaller particles. For
example, a particle size of the solid mixture may be reduced to
facilitate the separation process 20. In some embodiments, to
obtain a powder, the diatomaceous earth can be mildly milled or
ground, for example using a mortar and pestle, a jar mill, a rock
crusher, combinations thereof, and/or the like.
2. In some embodiments, components of the diatomaceous earth that
are larger than the diatom frustules or portions of diatom
frustules may be removed through a sieving step. In some
embodiments, the sieving step is performed after the diatomaceous
earth has been milled. For example, diatomaceous earth powder may
be sieved to remove the particles of the powder which are bigger
than the frustules. In some embodiments, the sieving can be
facilitated by dispersing the solid mixture (e.g., milled
diatomaceous earth) in a liquid solvent. The solvent may be water,
and/or other suitable liquid solvents. Dispersing the solid mixture
in the solvent may be facilitated by sonicating the mixture
comprising the solid mixture and the solvent. Other methods of
aiding dispersion may also be suitable. In some embodiments, the
dispersion comprises a weight percent of diatoms within a range of
from about 1 weight percent to about 5 weight percent, about 1
weight percent to about 10 weight percent, about 1 weight percent
to about 15 weight percent, or about 1 weight percent to about 20
weight percent. A concentration of the solid mixture in the
dispersion may be reduced to facilitate the sieving step to remove
particles of the dispersion that are larger than the diatoms. The
sieve openings depend on the size of diatoms in the sample. For
example, a suitable sieve may comprise a mesh size of about 20
microns, or any other mesh size that enables removal from the
dispersion particles of the solid mixture that are larger than the
diatoms (e.g., a sieve having a mesh size of about 15 microns to
about 25 microns, or of about 10 microns to about 25 microns). A
shaker sieve may be used for effectively increasing flow through
the sieve.
3. In some embodiments, the separation process includes a
purification step to remove organic contaminants from the diatoms
(e.g., diatom frustules or portions of diatom frustules). A
suitable process for removing organic contaminants may comprise
immersing and/or heating the diatoms in a bleach (e.g., nitric acid
and/or hydrogen peroxide), and/or annealing the diatoms at higher
temperatures. For example, a sample of diatoms may be heated in a
volume of a solution comprising about 10 volume percent to about 50
volume percent (e.g., 30 volume percent) hydrogen peroxide for
about 1 minute to about 15 minutes (e.g., 10 minutes). Other
compositions, concentrations and/or durations may be suitable. For
example, the composition of the solution used, the concentration of
the solution used, and/or the duration of the heating may depend on
the composition of the sample to be purified (e.g., types of
organic contaminants and/or diatoms). In some embodiments, the
diatoms can be heated in a solution until the solution ceases or
substantially ceases to bubble (e.g., indicating removal of organic
contaminants is complete or substantially complete) to facilitate
sufficient removal of the organic contaminants. Immersing and/or
heating diatoms in a solution may be repeated until organic
contaminants have been removed or substantially removed.
Purification of diatoms from organic contaminants may be followed
by washing with water. In some embodiments, the diatoms may be
washed with a liquid solvent (e.g., water). The diatoms may be
separated from the solvent through a sedimentation process,
including for example a centrifuge step. Suitable centrifuge
technology may include, for example, a disc stack centrifuge, a
decanter centrifuge, a tubular bowl centrifuge, combinations
thereof, and/or the like.
4. In some embodiments, the separation process includes a
purification step to remove inorganic contaminants. Inorganic
contaminants may be removed by mixing the diatoms with hydrochloric
and/or sulfuric acid. Inorganic contaminants may include
carbonates, clay, and other soluble non-silica materials. For
example, a sample of diatoms may be mixed with a volume of solution
comprising about 15 volume percent to about 25 volume percent of
hydrochloric acid (e.g., about 20 volume percent hydrochloric acid)
for a duration of about 20 minutes to about 40 minutes (e.g., about
30 minutes). Other compositions, concentrations and/or durations
may be suitable. For example, the composition of the solution used,
the concentration of the solution used, and/or the duration of the
mixing may depend on the composition of the sample to be purified
(e.g., types of inorganic contaminants and/or diatoms). In some
embodiments, the diatoms can be mixed in a solution until the
solution ceases or substantially ceases to bubble (e.g., indicating
removal of inorganic contaminants is complete or substantially
complete) to facilitate sufficient removal of the inorganic
contaminants. Mixing diatoms with a solution may be repeated until
inorganic contaminants have been removed or substantially
removed.
Purification of diatoms from soluble inorganic contaminants may be
followed by washing with water. In some embodiments, the diatoms
may be washed with a liquid solvent (e.g., water). The diatoms may
be separated from the solvent through a sedimentation process,
including for example a centrifuge step. Suitable centrifuge
technology may include, for example, a disc stack centrifuge, a
decanter centrifuge, a tubular bowl centrifuge, combinations
thereof, and/or the like.
5. In some embodiments, the separation process comprises dispersing
of frustules in a surfactant. The surfactant may facilitate
separation of the frustules and/or portions of frustules from one
another, reducing agglomeration of the frustules and/or portions of
frustules. In some embodiments, an additive is used to reduce
agglomeration of the diatoms. For example, diatoms may be dispersed
in a surfactant and an additive. In some embodiments, dispersing of
the diatoms in the surfactant and/or additive may be facilitated by
sonicating the mixture comprising diatoms, the surfactant and/or
the additive.
6. In some embodiments, broken frustule pieces may be extracted by
a wet sieving process. For example, a filtering process may be
used. In some embodiments, the filtering process comprises using a
sieve for removing the smaller pieces of broken frustules. The
sieve may comprise a mesh size suitable for removing the smaller
pieces of broken frustules (e.g., a 7 micron sieve). The wet
sieving process can inhibit or prevent small sediment from
accumulating in the pores of the sieve and/or allow small particles
to pass through the pores of the sieve, for example by disturbing
agglomeration of the sediment. Disturbing agglomeration may
include, for example, stirring, bubbling, shaking, combinations
thereof, and the like of materials which sediment on the sieve
mesh. In some embodiments, the filtering process can be continuous
through a series of sieves (e.g., having increasingly smaller pores
or mesh sizes) (e.g., multiple sieves in a machine having a single
input and output).
7. In some embodiments, a continuous centrifugation (milk
separator-type machine) of frustules in a liquid can be used. For
example, a disc stack centrifuge may be used. This process may be
used to separate the diatoms according to a common characteristic,
including for example, further separating broken frustule pieces
from the unbroken frustules. In some embodiments, disc stack
centrifuge step can be repeated to achieve a desired separation
(e.g., desired level of separation of the broken frustules from the
unbroken frustules).
8. As described herein, frustules may be washed in solvent,
followed by a sedimentation process (e.g. centrifugation) in order
to extract the frustules from the solvent. For example,
centrifugation can be used to sediment frustules or portions of
frustules after each washing step and/or before final use. Suitable
centrifuge technology for sedimenting frustules after a wash step
may include continuous centrifuges, including but not limited to a
disc stack centrifuge, a decanter centrifuge, and/or a tubular bowl
centrifuge.
The example separation procedure has been tested with fresh water
diatoms from Mount Silvia Pty, Ltd. Diatomite mining company,
Queensland, Australia. The majority of frustules in the sample has
one kind of diatoms Aulacoseira sp. The frustules have cylindrical
shape with diameter of about 5 microns and length from 10 to 20
microns.
Flow-chart of an example separation procedure, separation process
20 presented in FIGS. 4A and 4B only serves as an example. The
quantities of parameters in the flowchart are provided as
illustrative examples (e.g., suited to the chosen sample only). For
example, quantities may be different for different types of
diatoms.
The surface of diatoms can include amorphous silica and can include
silanol groups, which are negatively charged. Isoelectric point
found from zeta potential measurements can often be around pH2 for
diatoms (e.g., similar to that of amorphous silica).
In some embodiments, the surfactant can comprise a cationic
surfactant. Suitable cationic surfactants can include benzalkonium
chloride, cetrimonium bromide, lauryl methyl gluceth-10
hydroxypropyl dimonium chloride, benzethonium chloride,
benzethonium chloride, bronidox, dimethyldioctadecylammonium
chloride, tetramethylammonium hydroxide, mixtures thereof, and/or
the like. The surfactant may be a nonionic surfactant. Suitable
nonionic surfactants can include: cetyl alcohol, stearyl alcohol,
and cetostearyl alcohol, oleyl alcohol, polyoxyethylene glycol
alkyl ethers, octaethylene glycol monododecyl ether, glucoside
alkyl ethers, decyl glucoside, polyoxyethylene glycol octylphenol
ethers, Triton X-100, Nonoxynol-9, glyceryl laurate, polysorbate,
poloxamers, mixtures thereof, and/or the like.
In some embodiments, one or more additives can be added to reduce
agglomeration. Suitable additives may include: potassium chloride,
ammonium chloride, ammonium hydroxide, sodium hydroxide, mixtures
thereof, and/or the like.
Frustules may have one or more modifications applied to a surface
of the frustules. In some embodiments, frustules may be used as a
substrate to form one or more structures on one or more surfaces of
the frustules. FIG. 5A shows an example frustule 50 comprising
structures 52. For example, a frustule 50 may have a hollow
cylindrical or substantially cylindrical shape, and may comprise
structures 52 on both an exterior and interior surface of the
cylinder. The structures 52 may modify or affect a characteristic
or attribute of the frustule 50, including, for example, the
conductivity of the frustule 50. For example, an electrically
insulating frustule 50 may be made electrically conductive by
forming electrically conductive structures 52 on one or more
surfaces of the frustule 50. A frustule 50 may include structures
52 comprising silver, aluminum, tantalum, brass, copper, lithium,
magnesium, combinations thereof, and/or the like. In some
embodiments, a frustule 50 includes structures 52 comprising ZnO.
In some embodiments, a frustule 50 includes structures 52
comprising an oxide of manganese, such as manganese dioxide
(MnO.sub.2), manganese (II, III) oxide (Mn.sub.3O.sub.4), manganese
(II) oxide (MnO), manganese (III) oxide (Mn.sub.2O.sub.3), and/or
manganese oxyhydroxide (MnOOH). In some embodiments, a frustule 50
includes structures 52 comprising other metal-containing compounds
or oxides. In some embodiments, a frustule 50 includes structures
52 comprising a semiconductor material, including silicon,
germanium, silicon germanium, gallium arsenide, combinations
thereof, and/or the like. In some embodiments, frustules 50
comprise surface modifying structures 52 on all or substantially
all of the surfaces of the frustules 50.
Structures 52 applied or formed on a surface of a frustule 50 may
comprise various shapes, dimensions, and/or other attributes. A
frustule 50 may comprise structures 52 having a uniform or
substantially uniform shape, dimension, and/or another structure 52
attribute. In some embodiments, a frustule 50 may have structures
52 comprising nanowires, nanotubes, nanosheets, nanoflakes,
nanospheres, nanoparticles, structures having a rosette shape,
combinations thereof, and/or the like. In some embodiments, a
nanostructure can have a dimension having a length of about 0.1
nanometers (nm) to about 1000 nm. In some embodiments, the
dimension is a diameter of the nanostructure. In some embodiments,
the dimension is a longest dimension of the nanostructure. In some
embodiments, the dimension is a length and/or width of the
nanostructure. Nanostructures on surfaces of frustules may
facilitate materials having increased surface area, advantageously
providing materials having increased surface area on which
electrochemical reaction can occur. In some embodiments, diatom
frustules can reduce, prevent, or substantially prevent
agglomeration of nanostructures in manufacturing processes and/or
in products fabricated by the manufacturing processes (e.g., in an
electrode fabricated using diatom frustules, devices comprising
such an electrode). Reduction in agglomeration of nanostructures
may facilitate providing increased active surface area for
electrolyte to access (e.g., increase active surface area of an
electrode, better electrical performance of a device comprising
such an electrode). In some embodiments, the porosity of surfaces
of diatom frustules can facilitate electrolyte access to the active
surface area, such as facilitating diffusion of electrolytic ions
to active surfaces of an electrode (e.g., diatom frustules can have
pore sizes of about 1 nanometers (nm) to about 500 nm).
In some embodiments, the frustule 50 can be thickly covered by the
nanostructures 52. In some embodiments, a ratio of a mass of the
nanostructures 52 to a mass of the frustule 50 is between about 1:1
and about 20:1, between about 5:1 and about 20:1, or between about
1:1 and about 10:1. The nanostructures 52 preferably have a mass
greater than a mass of the frustule 50 prior to coating. The mass
of the nanostructures 52 may be determined by weighing the
frustules 50 before and after coating with the difference being the
mass of the nanostructures 52.
Structures 52 can be formed or deposited onto a surface of a
frustule 50 at least in part by combining a frustule 50 with a
formulation comprising a desired material to allow coating or
seeding of the structures 52 onto a surface of the frustule 50.
As described herein, structures 52 on a surface of the frustule 50
may comprise zinc oxide, such as zinc oxide nanowires. In some
embodiments, zinc oxide nanowires can be formed on a surface of the
frustule 50 by combining the frustule 50 with a solution comprising
zinc acetate dihydrate (Zn(CH.sub.3CO.sub.2).sub.2.2H.sub.2O) and
ethanol. For example, a solution having a concentration of 0.005
mol/L (M) zinc acetate dihydrate in ethanol may be combined with
frustules 50 so as to coat a surface of the frustules 50. The
coated frustules 50 may then be air dried and rinsed with ethanol.
In some embodiments, the dried frustules 50 can then be annealed
(e.g., at a temperature of about 350.degree. C.). The zinc oxide
nanowires may then be allowed to grow on the coated surface of the
frustules 50. In some embodiments, the annealed frustules 50 are
maintained at a temperature above room temperature (e.g.,
maintained at around a temperature of about 95.degree. C.) to
facilitate formation of the zinc oxide nanowires.
Frustules 50 may also comprise a material formed on or deposited
onto a surface of the frustules 50 to modify a characteristic or
attribute of the frustules 50. For example, an electrically
insulating frustule 50 may be made electrically conductive by
forming or applying an electrically conductive material on one or
more surfaces of the frustule 50. A frustule 50 may include a
material comprising silver, aluminum, tantalum, brass, copper,
lithium, magnesium, combinations thereof, and/or the like. In some
embodiments, a frustule 50 includes material comprising ZnO. In
some embodiments, a frustule 50 includes material comprising an
oxide of manganese. In some embodiments, a frustule 50 includes a
material comprising a semiconductor material, including silicon,
germanium, silicon germanium, gallium arsenide, combinations
thereof, and/or the like. The surface modifying material may be on
an exterior surface and/or an interior surface of the frustules 50.
In some embodiments, frustules 50 comprise a surface modifying
material on all or substantially all of the surfaces of the
frustules 50.
A material can be formed or deposited onto a surface of a frustule
50 in part through combining a frustule 50 with a formulation
including a desired material to allow coating or seeding of the
material onto a surface of the frustule 50.
As described herein, a material may be deposited onto a surface of
the frustule 50. In some embodiments, the material comprises a
conductive metal such as silver, aluminum, tantalum, copper,
lithium, magnesium, and brass. In some embodiments, coating a
surface of the frustule 50 with a material comprising silver
includes, at least in part, combining the frustule 50 with a
solution comprising ammonia (NH.sub.3) and silver nitrate
(AgNO.sub.3). In some embodiments, the solution can be prepared in
a process similar to a process often used in preparing Tollens'
reagent. For example, preparation of the solution may comprise
addition of ammonia to aqueous silver nitrate to form a
precipitate, followed by further addition of ammonia until the
precipitate dissolves. The solution may then be combined with the
frustule 50. As an example, 5 milliliters (mL) of ammonia may be
added to 150 mL of aqueous silver nitrate while stirring such that
a precipitate forms, followed by addition of another 5 mL of
ammonia until the precipitate dissolves. A mixture may then be
formed by combining the solution with 0.5 grams (g) of frustules 50
and an aqueous solution of glucose (e.g., 4 g of glucose dissolved
in 10 mL of distilled water). The mixture may then be placed into a
container immersed in a bath maintained at a temperature (e.g., a
warm water bath maintained at a temperature of about 70.degree. C.)
so as to facilitate the coating of the frustules
50.
Growing Nanostructures on Diatom Frustules or Portions of Diatom
Frustules
As described herein, diatomaceous earth is naturally occurring
sediment from fossilized microscopic organisms called diatoms. The
fossilized microorganisms comprise hard frustules made from highly
structured silica with sizes often between about 1 micron and about
200 microns. Different species of diatoms have different 3D shapes
and features, which vary from source to source.
Diatomaceous earth can include a highly porous, abrasive, and/or
heat resistant material. Due to these properties, diatomaceous
earth has found wide applications including filtering, liquid
absorption, thermal isolation, as ceramic additive, mild abrasive,
cleaning, food additive, cosmetics, etc.
Diatom frustules have attractive features for nanoscience and
nanotechnology--they have naturally occurring nanostructures:
nanopores, nanocavities and nanobumps (e.g., as shown in FIGS. 1 to
3). The abundance of frustule shapes depending on the diatom
species (e.g., more than 105) is another attractive property.
Silicon dioxide, from which the diatom frustules are made, can be
coated or replaced by a useful substance while preserving the
diatom nanostructures. Diatom nanostructures may serve as a useful
nanomaterial for many processes and devices: dye-sensitized solar
cells, drug delivery, electroluminescent displays, anode for Li-ion
batteries, gas sensors, biosensors, etc. Formation of MgO,
ZrO.sub.2, TiO.sub.2, BaTiO.sub.3, SiC, SiN, and Si may be
accomplished using high temperature gas displacement of
SiO.sub.2.
In some embodiments, diatom frustules can be coated with 3D
nanostructures. The diatoms may be coated on inner and/or outer
surfaces, including inside the nanopores of the diatoms. The
coatings may not preserve the diatom structure precisely. However,
coatings may themselves have nanopores and nanobumps. Such silica
frustules/nanostructures composites use frustules as support. The
nanostructured material may have small nanoparticles densely joined
together: nanowires, nanospheres, nanoplates, dense array of
nanoparticles, nanodisks, and/or nanobelts. Overall, the composites
may have a very high surface area.
Nanostructures comprising various materials may be formed on
surfaces of frustules. In some embodiments, nanostructures comprise
a metallic material. For example, nanostructures formed on one or
more surfaces of a frustule may comprise zinc (Zn), magnesium (Mg),
aluminum (Al), mercury (Hg), cadmium (Cd), lithium (Li), sodium
(Na), calcium (Ca), iron (Fe), lead (Pb), nickel (Ni), silver (Ag),
combinations thereof, and/or the like. In some embodiments,
nanostructures comprise metal oxides. For example, nanostructures
formed on a frustule surface may comprise zinc oxide (ZnO),
manganese dioxide (MnO.sub.2), manganese(II, III) oxide
(Mn.sub.3O.sub.4), manganese(II) oxide (MnO), manganese(III) oxide
(Mn.sub.2O.sub.3), mercury oxide (HgO), cadmium oxide (CdO), silver
(I,III) oxide (AgO), silver(I) oxide (Ag.sub.2O), nickel oxide
(NiO), lead(II) oxide (PbO), lead(II, IV) oxide (Pb.sub.2O.sub.3),
lead dioxide (PbO.sub.2), vanadium(V) oxide (V.sub.2O.sub.5),
copper oxide (CuO), molybdenum trioxide (MoO.sub.3), iron(III)
oxide (Fe.sub.2O.sub.3), iron(II) oxide (FeO), iron(II, III) oxide
(Fe.sub.3O.sub.4), rubidium(IV) oxide (RuO.sub.2), titanium dioxide
(TiO.sub.2), iridium(IV) oxide (IrO.sub.2), cobalt(II, III) oxide
(Co.sub.3O.sub.4), tin dioxide (SnO.sub.2), combinations thereof,
and/or the like. In some embodiments, nanostructures comprise other
metal-containing compounds, including for example, manganese(III)
oxohydroxide (MnOOH), nickel oxyhydroxide (NiOOH), silver nickel
oxide (AgNiO.sub.2), lead(II) sulfide (PbS), silver lead oxide
(Ag.sub.5Pb.sub.2O.sub.6), bismuth(III) oxide (Bi.sub.2O.sub.3),
silver bismuth oxide (AgBiO.sub.3), silver vanadium oxide
(AgV.sub.2O.sub.5), copper(I) sulfide (CuS), iron disulfide
(FeS.sub.2), iron sulfide (FeS), lead(II) iodide (PbI.sub.2),
nickel sulfide (Ni.sub.3S.sub.2), silver chloride (AgCl), silver
chromium oxide or silver chromate (Ag.sub.2CrO.sub.4), copper(II)
oxide phosphate (Cu.sub.4O(PO.sub.4).sub.2), lithium cobalt oxide
(LiCoO.sub.2), metal hydride alloys (e.g., LaCePrNdNiCoMnAl),
lithium iron phosphate (LiFePO.sub.4 or LFP), lithium permanganate
(LiMn.sub.2O.sub.4), lithium manganese dioxide (LiMnO.sub.2),
Li(NiMnCo)O.sub.2, Li(NiCoAl)O.sub.2, cobalt oxyhydroxide (CoOOH),
titanium nitride (TiN), combinations thereof, and/or the like.
In some embodiments, nanostructures formed on surfaces of frustules
can comprise non-metallic or organic material. In some embodiments,
the nanostructures can comprise carbon. For example, the
nanostructures may comprise multi-wall and/or single-wall carbon
nanotubes, graphene, graphite, carbon nano-onions, combinations
thereof, and/or the like. In some embodiments, nanostructures may
comprise fluorocarbons (e.g., CF.sub.x), sulfur (S), conductive
n/p-type doped polymers (e.g., conductive n/p-type doped
poly(fluorene)s, polyphenylenes, polypyrenes, polyazulenes,
polynaphthalenes, poly(pyrrole)s, polycarbazoles, polyindoles,
polyazepines, polyanilines, poly(thiophene)s,
poly(3,4-ethylenedioxythiophene), and/or poly(p-phenylene
sulfide)), combinations thereof, and/or the like.
Nanostructures formed on a surface of a diatom frustule may
include: 1) silver (Ag) nanostructures; 2) zinc-oxide (ZnO)
nanostructures; 3) carbon nanotubes "forest;" and/or 4)
manganese-containing nanostructures. As described herein, the
diatom frustules having nanostructures formed on one or more of
their surfaces can be used for energy storage devices such as
batteries and supercapacitors, solar cells, and/or gas sensors.
Nanostructures may be formed on one or more surfaces of unbroken
frustules and/or broken frustules. In some embodiments, frustules
or portions of frustules used in the nanostructure formation
process may have been extracted through a separation procedures
comprising separation steps described herein (e.g., the separation
process 20 shown in FIGS. 4A and 4B). In some embodiments, before
the growth of nanostructured active materials, frustules can be
pretreated with one or more functionalized chemicals (e.g.,
siloxanes, fluorosiloxanes, proteins, and/or surfactants). In some
embodiments, before the growth of nanostructured active materials,
frustules can be pre-coated with a conductive materials (e.g.,
metal, and/or a conductive carbon), and/or a semiconductor
material. For example, frustules may be pre-coated with silver
(Ag), gold (Au), copper (Cu), nickel (Ni), platinum (Pt), graphene,
graphite, carbon nanotubes, silicon (Si), germanium (Ge)), a
semiconductor-containing alloy (e.g., an aluminum-silicon (AlSi)
alloy), combinations thereof, and/or the like.
In some embodiments, nanostructures are grown using two step
approaches. The first step generally includes the growth of seeds
on the surface of diatom frustules. Seeds are nanostructures that
are directly bonded (e.g., chemically bonded) to the surfaces of
the diatom frustules, and may have certain grain size and/or
uniformity. Energy may be provided to create such bonds. The
seeding process may be conducted under high temperatures and/or
involve other techniques that can create heat or some other form of
energy gain.
A second step of forming nanostructures generally includes growing
the final nanostructures from the seeds. Frustules pre-coated with
seeds may be immersed in environments of initial materials under
certain conditions. The nanostructures may include one or more of
nanowires, nanoplates, dense nanoparticles, nanobelts, nanodisks,
combinations thereof, and/or the like. The form factor may depend
on conditions of the growth of the nanostructures (e.g., morphology
of the nanostructures can depend on one or more growth conditions
during forming of the nanostructures on the seed layer, including
for example a growth temperature, a pattern of heating, inclusion
of a chemical additive during the nanostructure growth, and/or
combinations thereof).
An Example Process of Forming Ag Nanostructures on Surfaces of
Diatom Frustules
The initial coating of silica with silver (or seeding) can be
realized by reduction of a Ag.sup.+ salt using microwave,
ultrasonication, surface modification, and/or reduction of silver
nitrate (AgNO.sub.3) with a reducing agent.
The seed growth step may include dissolution of a silver salt and a
reducing agent in a solvent (e.g., the reducing agent and the
solvent can be the same substance) and dispersing purified diatoms
in the mixture. During and/or after the dissolution, a physical
force like mixing, stirring, heating, ultrasonication, microwaves,
combinations thereof, and/or the like may be applied. The seed
layer growth process may occur for various amounts of time.
Examples of Growing Ag Seeds on Surfaces of Diatom Frustules
Example 1 includes the following steps: 0.234 g of purified
diatoms, 0.1 g AgNO.sub.3, and 50 mL of molten at 60.degree. C. PEG
600 (polyethylene glycol) are mixed in a beaker. In some
embodiments, a mixture comprising clean diatoms, a silver
contributing component (e.g., silver nitrate), and a reducing agent
may be heated by a cyclic heating regimen. In some embodiments, the
reducing agent and the solvent can be the same substance. For
example, a mixture may be heated for about 20 minutes to about 40,
alternating the heat from about 100 Watt to about 500 Watt every
minute. For example, the mixture comprising cleaned diatoms, silver
nitrate, and molten PEG was heated by microwave for about 30 min.
The microwave power was altered from 100 to 500 Watt every minute
to prevent overheating the mixture. Some commercial microwaves
allow the user to determine the temperature of the contents after a
certain duration, and/or to determine multiple temperatures after
various durations (e.g., to define a temperature ramp), during
which the microwave controls the power in order to achieve that
result. For example, the microwave may determine that a lower power
is needed to heat 50 mL of water to 85.degree. C. in 2 min than to
heat 50 mL of water to 85.degree. C. in 1 min, and this adjustment
may be made during the heating process, for example based on
temperature sensors. For another example, the microwave may
determine that a lower power is needed to heat 50 mL of water to
85.degree. C. in 2 min than to heat 100 mL of water to 85.degree.
C. in 2 min, and this adjustment may be made during the heating
process, for example based on temperature sensors. The diatoms were
centrifuged and washed with ethanol. The seeds are illustrated in
FIGS. 5B and 5C.
Example 2 includes the following steps: Mix 45 mL of
N,N-dimethylformamide, 0.194 g of 6,000 MW PVP
(polyvinylpyrrolidone), 5 mL of 0.8 mM AgNO.sub.3 in water, and 0.1
g of filtered and purified diatoms in a beaker. A tip of an
ultrasonic processor (e.g., 13 mm diameter, 20 kHz, 500 Watt) is
placed in the mixture and the beaker with the mixture placed in an
ice bath. Tip amplitude is set at 100%. Sonication lasts 30 min.
The diatoms are cleaned after the procedure in ethanol two times
using bath sonication and centrifugation at 3,000 RPM for 5 min.
Then the process is repeated two more times until seeds are seen on
the diatoms.
FIG. 5B shows a SEM image, at 50 k.times. magnification, of silver
seeds 62 formed on a surface of a diatom frustule 60. FIG. 5C shows
a SEM image, at 250 k.times. magnification, of the silver seeds 62
formed on the surface of the diatom frustule 60.
Example of Forming Silver Nanostructures on Silver Seeded Diatom
Frustule Surfaces
Further coating of the seeded frustules with silver may be
conducted under argon (Ar) atmosphere to inhibit formation of
silver oxides. In some embodiments, diatom frustule portions can be
sintered (e.g., heated to a temperature of about 400.degree. C. to
about 500.degree. C.) to obtain silver from silver oxides which may
have formed on one or more surfaces of diatom frustule portions,
including silver oxides formed during the process to further coat
the seeded diatom frustule portions with silver. For example,
sintering of diatom frustule portions may be performed on diatom
frustule portions used in fabricating a conductive silver ink
(e.g., a UV-curable conductive silver ink as described herein). In
some embodiments, the sintering may be under an atmosphere
configured to promote reduction of silver oxides to silver (e.g.,
hydrogen gas). Sintering the diatom frustule portions that the
conductive silver ink comprises to obtain silver from silver oxides
may improve conductivity of the conductive silver ink, for example
because silver is more conductive than silver oxide and/or because
silver-silver contact (e.g., as opposed to silver-silver oxide
contact and/or silver oxide-silver oxide contact) may be increased.
Other methods of obtaining silver from silver oxide may also be
suitable in place of or in combination with sintering, including,
for example, a process comprising a chemical reaction.
Formation of nanostructures on the seed layer may include a silver
salt, a reducing agent, and a solvent. A mixing step, a heating
step, and/or a titration step (e.g., to facilitate interaction of
components of the nanostructure growth process) may be applied to
form the nanostructures on the seed layer.
An example of process for forming the nanostructures on the seed
layer (e.g., forming a thick silver coating) includes the following
process:
5 mL of 0.0375 M PVP (6,000 MW) solution in water is placed in one
syringe and 5 mL of 0.094 M AgNO.sub.3 solution in water is placed
in another syringe. 0.02 g of seeded washed and dried diatoms mixed
with 5 mL of ethylene glycol heated to about 140.degree. C. The
diatoms are titrated with silver salt (e.g., AgNO.sub.3) and PVP
solutions at a rate of about 0.1 milliliter per minute (mL/min)
using a syringe pump. After the titration is finished, the mixture
is stirred for about 30 min. Then diatoms are washed (e.g., washed
two times) using ethanol, bath sonication, and centrifugation.
FIGS. 5D and 5E show SEM images of an example where silver
nanostructures 64 have formed on a surface of diatom frustule 60.
FIGS. 5D and 5E show a frustule 60 having a thick nanostructured
coating with high surface area. FIG. 5D is a SEM image of the
frustule surface at 20 k.times. magnification, while FIG. 5E shows
a SEM image of the frustule surface at 150 k times magnification.
FIG. 5L is another SEM image, at 50 k.times. magnification, of the
diatom frustule 60 having silver nanostructures 64 on a surface.
The thick nanostructured coating of diatom frustule 60 can be seen
in FIG. 5L.
Examples of suitable reducing agents for Ag growth include common
reducing agents used for silver electroless deposition. Some
suitable reducing agents for silver electroless deposition include
hydrazine, formaldehyde, glucose, sodium tartrate, oxalic acid,
formic acid, ascorbic acid, ethylene glycol, combinations thereof,
and/or the like.
Examples of suitable Ag.sup.+ salts and oxides include silver
salts. The most commonly used silver salts are soluble in water
(e.g., AgNO.sub.3). Suitable silver salts may include an ammonium
solution of AgNO.sub.3 (e.g., Ag(NH.sub.3).sub.2NO.sub.3). In some
embodiments, any silver (I) salt or oxide can be used (e.g.,
soluble and/or not soluble in water). For example, silver oxide
(Ag.sub.2O), silver chloride (AgCl), silver cyanide (AgCN), silver
tetrafluoroborate, silver hexafluorophosphate, silver
ethylsulphate, combinations thereof, and/or the like, may also be
suitable.
Suitable solvents may include: water, alcohols such as methanol,
ethanol, N-propanol (including 1-propanol, 2-propanol (isopropanol
or IPA), 1-methoxy-2-propanol), butanol (including 1-butanol,
2-butanol (isobutanol)), pentanol (including 1-pentanol,
2-pentanol, 3-pentanol), hexanol (including 1-hexanol, 2-hexanol,
3-hexanol), octanol, N-octanol (including 1-octanol, 2-octanol,
3-octanol), tetrahydrofurfuryl alcohol (THFA), cyclohexanol,
cyclopentanol, terpineol; lactones such as butyl lactone; ethers
such as methyl ethyl ether, diethyl ether, ethyl propyl ether, and
polyethers; ketones, including diketones and cyclic ketones, such
as cyclohexanone, cyclopentanone, cycloheptanone, cyclooctanone,
acetone, benzophenone, acetylacetone, acetophenone, cyclopropanone,
isophorone, methyl ethyl ketone; esters such ethyl acetate,
dimethyl adipate, propylene glycol monomethyl ether acetate,
dimethyl glutarate, dimethyl succinate, glycerin acetate,
carboxylates; carbonates such as propylene carbonate; polyols (or
liquid polyols), glycerols and other polymeric polyols or glycols
such as glycerin, diol, triol, tetraol, pentanol, ethylene glycols,
diethylene glycols, polyethylene glycols, propylene glycols,
dipropylene glycols, glycol ethers, glycol ether acetates
1,4-butanediol, 1,2-butanediol, 2,3-butanediol, 1,3-propanediol,
1,4-butanediol, 1,5-pentanediol, 1,8-octanediol, 1,2-propanediol,
1,3-butanediol, 1,2-pentanediol, etohexadiol, p-menthane-3,8-diol,
2-methyl-2,4-pentanediol; tetramethyl urea, n-methylpyrrolidone,
acetonitrile, tetrahydrofuran (THF), dimethyl formamide (DMF),
N-methyl formamide (NMF), dimethyl sulfoxide (DMSO); thionyl
chloride; sulfuryl chloride, combinations thereof, and/or the
like.
In some embodiments, a solvent can also act as a reducing
agent.
Example Method of Fabricating a Low-Cost UV-Curable Silver-Diatom
Conductive Ink
Thermally curable silver flake and silver nanoparticle conductive
inks are available from a variety of manufacturers such as Henkel
Corp., Spraylat Corp., Conductive Compounds, Inc., DuPont, Inc.,
Creative Materials Corp., et al. A much less common product is a
silver conductive ink curable with ultraviolet (UV) light. Only a
few suppliers, (e.g., Henkel Corp.) have such inks in their product
offerings. UV-curable silver conductive inks often can be very
costly because of the high silver loading, and high cost per square
meter relative to the conductivity. The conductivities can be as
much as 5 to 10 times lower than thermally cured silver conductive
inks applied at the same wet film thickness.
There is clearly a need for a low-cost UV-curable silver with at
least the same or better conductivity than the currently available
UV-curable inks. Some UV-curable silvers may not take full
advantage of the volume of silver present in the ink, so there is a
need to develop a silver ink using much less silver that has
similar or better conductivity and/or curability than current
UV-curable silver inks.
A difficulty with developing UV-curable silvers may be due to the
UV absorption properties of silver. In thermally-cured silver inks,
silver flakes having a high aspect ratio may be used to produce the
highest conductivity by maximizing the inter-flake contact area. If
this type of silver flake is mixed with a UV-curable resin system
appropriate for a conductive ink, applied to a surface using
printing or other coating processes, and then exposed to UV light,
most of the UV light may be absorbed by the silver before the UV
light can scatter through the wet layer of silver ink. UV
absorption by silver flakes can impede or prevent UV
light-initiated polymerization from occurring in the wet ink film
(e.g., impeding or preventing UV light-initiated polymerization of
the wet ink beyond a certain depth). Reduced polymerization of the
ink film may result in an incompletely cured layer of silver ink
that may not adhere to the substrate, for example due to the
bottom-most portions of the silver ink layer being uncured and wet.
Lower aspect-ratio silver particles may be used in UV-curable
silver inks to obtain suitable curing throughout the applied layer
of silver ink by increasing the number of possible light scattering
paths through the applied layer of silver ink. The low aspect-ratio
particles have decreased surface area, which may reduce inter-flake
contact area, and in turn may reduce conductivity of the cured film
relative to what would be possible if a high aspect-ratio flake was
used. If this curing problem could be solved, larger aspect ratio
silver flake with higher conductivity could be used in the silver
ink, which may improve conductivity of the resulting silver film
and/or reduce the amount of silver used to achieve a high
conductivity.
In some embodiments, a non-conducting substrate (e.g., a diatom
frustule portion, such a diatom frustule flake) can be plated with
silver. UV light may pass through the perforations on one or more
surfaces of the body of the diatom frustule flake. Using the silver
plated diatom flake in the silver ink may facilitate curing of the
silver ink, enabling the use of high aspect ratio flakes in the
silver ink. In some embodiments, a silver ink comprising silver
plated diatom frustules may enable increased conductivity of the
cured silver ink while, at the same time, reducing the cost of the
ink.
In some embodiments, the portions of diatom frustules (e.g., broken
diatom frustules) used in the silver ink can be purified and
separated from the intact diatom particles, and one or more
surfaces of the portions of diatom frustules may be electrolessly
coated with silver, for example according to methods described
herein.
A diatom surface may be perforated by a regular pattern of holes or
openings (e.g., including holes approximately 300 nm in diameter),
even when coated with silver. The openings may be large enough to
allow UV wavelengths to scatter through the silver coated diatom
particles. Broken diatoms coated with silver may comprise shards in
the form of high aspect-ratio perforated flakes. FIG. 5F shows a
SEM image of a broken piece of diatom frustule (e.g., a diatom
frustule flake 60A) coated with Ag nanostructures (e.g., silver
nanostructures 64).
In some embodiments, a silver coated perforated diatom flake can be
used for making a UV-silver ink which can be cured when a
moderately thickly ink is used (e.g., a silver ink having a
thickness of about 5 .mu.m to about 15 .mu.m), even though the
conductive particles have high aspect-ratios and therefore large
surface areas. Large surface areas of the frustule flake may create
excellent inter-flake conductivity by increasing the number of
inter-flake electrical contacts, resulting in a highly conductive
ink that uses substantially only as much silver as is needed to
achieve the desired sheet conductivity, with the rest of the volume
taken up by the inexpensive diatom filler material and UV binder
resin.
The silver nanostructure may cover substantially all surfaces of
the frustules, including the inner surfaces of the frustule
perforations, but without blocking the perforations (e.g., one or
more surfaces of the perforations and frustule surfaces may be
plated with silver nanostructures and/or a silver seed layer). The
perforations in the Ag coated diatom flakes may allow UV radiation
to pass through the diatom flakes, facilitating curing to a deep
depth within the applied silver ink films while allowing current to
be conducted directly from one side of the flake to the other
through the perforations. A reduction in the length of the
conduction pathways through the flake may reduce the overall
resistance of the cured film made from the silver ink.
An example UV light-induced polymerizable ink formulation may
include components from the following list. In some embodiments, a
silver ink having diatom frustule flakes can be fabricated by
combining components listed below, including, for example,
combining a plurality of frustule portions (e.g., frustule flakes)
having silver nanostructures formed on one or more surfaces with
one or more other silver ink components listed below. A silver film
may be fabricated by curing the silver ink with a UV light
source.
1) Diatoms, any of a variety of species, plated (e.g., having
nanostructure formed thereon) with between about 10 nm and about
500 nm thick Ag coating. A thickness of the Ag coating may depend
on a pore size of the diatom perforations. Ratios in the
formulation may be between about 50% and about 80% by weight. An
example diatom species whose fragments can be used is Aulacoseira
sp. 1.
2) A polar vinyl monomer with good affinity for silver, such as
n-vinyl-pyrrolidone or n-vinylcaprolactam.
3) An acrylate oligomer with good elongation properties as a
rheology modifier and to improve flexibility in the cured film.
4) One or more difunctional or trifunctional acrylate monomers or
oligomers as crosslinking agents to produce a tougher, more solvent
resistant cured film through increased cross-linking. These
materials may be chosen to function as photoinitiation synergists,
which may improve surface curing. Examples may include ethoxylated
or propoxylated hexandiol acrylates such as Sartomer CD560.RTM.,
ethoxylated trimethylpropane triacrylate available, for example
from Sartomer under the product code SR454.RTM., or triallyl
cyanurate available, for example from Sartomer under the product
code SR507A.RTM.. Acrylated amine synergists may be an option, and
examples may include Sartomer CN371.RTM. and Sartomer
CN373.RTM..
5) An acrylate-based flow and level agent to reduce bubbling and
improve wet ink quality (e.g., suitable flow and level agents may
include Modaflow 2100.RTM., Modaflow 9200.RTM.). Improved wet ink
quality may, in turn, improve cured silver ink film quality.
6) One or more photoinitiators appropriate for pigment loaded ink
systems. In some embodiments, at least one of the photoinitatiors
is sensitive to wavelengths near to or smaller than the silver
plated diatom flake's average pore size so that UV photons may pass
through the pore in order to initiate polymerization underneath the
flake and/or scatter through a perforation in another silver plated
diatom flake to penetrate even deeper into the uncured film to
initiate polymerization there. Examples of photoinitiators can
include Ciba Irgacure 907.RTM. and Isopropyl thioxanthoone (ITX,
available from Lambson, UK under the tradename Speedcure ITV)).
7) An optional adhesion promoting acrylate (e.g., 2-carboxyethyl
acrylate).
8) A optional wetting agent to lower surface tension and improve
flake wetting (e.g., DuPont Capstone FS-30.RTM. and DuPont Capstone
FS-31.RTM.).
9) An optional UV stabilizer to suppress premature polymerization
triggered by the presence of silver metal (e.g., hydroquinone and
methyl ethyl hydroquinone (MEHQ)).
10) An optional low boiling point solvent for lowering viscosity to
facilitate the silver ink formulation being used in high speed
coating processes, including processes such flexographic printing,
gravure printing, combinations thereof, and/or the like.
In some embodiments, a silver ink comprising diatom frustule
portions can be thermally cured. In some embodiments, the silver
ink can be exposed to a heat source. For example, the silver ink
may be heated to facilitate a polymerization reaction between
polymer components of the silver ink. In some embodiments, thermal
curing of the silver ink can facilitate removal of a solvent
component. For example, the silver ink can be exposed to a heat
source to raise a temperature of the silver ink above a boiling
point of the silver ink solvent component to facilitate removal of
the solvent component.
Example Processes of Forming Zinc-Oxide (ZnO) Nanostructures on
Surfaces of Diatom Frustules
Generally, the ZnO seeds on a substrate can be deposited using
spray or spin coating of colloidal ZnO or with thermal
decomposition of zinc salts solutions. For example, thermal
decomposition of zinc acetate precursor can give vertically
well-aligned ZnO nanowires.
Growth of ZnO nanostructures from seeds may be realized by the
hydrolysis of Zn salts in a basic solution. The process can be
performed at room temperature or at higher temperatures. Microwave
heating can significantly accelerate growth of nanostructures.
Depending on growth parameters, different nanostructures were
observed (e.g., morphology of the nanostructures can depend on one
or more growth conditions during forming of the nanostructures on
the seed layer, including for example a growth temperature, a
pattern of heating, inclusion of a chemical additive during the
nanostructure growth, and/or combinations thereof). For example, a
chemical additive may be used to achieve a desired morphology of
nanostructures. ZnO nanostructures also can be doped to control
their semiconducting properties.
Example Processes for Growing ZnO Seeds on Surfaces of Diatom
Frustules
1. Building seeds of ZnO can be realized by heating a mixture of
0.1 g of purified diatoms and 10 mL of 0.005 M zinc acetate
(Zn(CH.sub.3COO).sub.2) (e.g., a zinc contributing component) in
ethanol to about 200.degree. C. (e.g., including from about
175.degree. C. to about 225.degree. C.) until dry. SEM images, each
at 100 k.times. magnification, of a ZnO seeded frustule surface are
shown in FIGS. 5G and 5H. FIGS. 5G and 5H show SEM images of seeds
72 comprising ZnO formed on a surface of a frustule 70. FIG. 5G
shows a SEM image, at 100 k.times. magnification, of a frustule
surface having seeds 72 comprising zinc-oxide. FIG. 5H shows a SEM
image, at 100 k.times. magnification, of a frustule surface having
seeds 72 comprising zinc-oxide.
In some embodiments, a process of seeding frustule surfaces with
ZnO comprises forming a mixture comprising the following
composition: about 2 weight % to about 5 weight % frustules, about
0.1 weight % to about 0.5 weight % of zinc salt (e.g.,
Zn(CH.sub.3COO).sub.2), and about 94.5 weight % to about 97.9
weight % of an alcohol (e.g., ethanol). In some embodiments,
forming the ZnO seeds on the frustule surfaces comprises heating
the mixture. The mixture may be heated to a desired temperature for
a period of time to facilitate formation of ZnO seeds on surfaces
of the frustules and removal of liquids from the mixture. Heating
may be performed using any number of heating apparatuses capable of
heating the mixture to the desired temperature for the desired
period of time, such as a hot plate. In some embodiments, the
mixture can be heated to a temperature of greater than about
80.degree. C. to facilitate formation of ZnO seeds on the frustule
surfaces and to dry the ZnO seeded frustules. In some embodiments,
the heated mixture may be further heated in a vacuum oven to
facilitate further removal of liquids. For example, the mixture may
be heated in a vacuum oven at a pressure of about 1 millibar (mbar)
and at a temperature of about 50.degree. C. to about 100.degree.
C.
In some embodiments, the dried frustules can be subjected to an
annealing process. In some embodiments, the annealing process can
be configured to facilitate desired formation of ZnO, for example
by facilitating decomposition of the zinc salt to form ZnO. In some
embodiments, conditions of the annealing process can be configured
to achieve further drying of the frustules, such as by evaporation
of any remaining liquids from the frustules. In some embodiments,
the annealing process can comprise heating the dried frustules in
an inert atmosphere at a temperature of about 200.degree. C. to
about 500.degree. C. In some embodiments, the annealing process can
include heating in an atmosphere comprising argon gas (Ar) and/or
nitrogen gas (N.sub.2).
Example Processes for Growing ZnO Nanostructures on ZnO Seeded
Surfaces of Diatom Frustules
2. As described herein, ZnO nanostructures can be grown on the ZnO
seeds formed on frustule surfaces. In some embodiments, ZnO
nanostructure growth can be conducted in mixture of 0.1 g seeded
frustules with 10 mL of 0.025 M ZnNO.sub.3 (e.g., a zinc
contributing component) and 0.025 M hexamethylenetetramine solution
(e.g., a basic solution) in water. The mixture can be heated to
about 90.degree. C. (e.g., including from about 80.degree. C. to
about 100.degree. C.) for about two hours (e.g., including from
about one hour to about three hours) on a stir plate, or by using a
cyclic heating routine (e.g., microwave heating) for a duration of
about 10 min (e.g., including for a duration of about 5 minutes to
about 30 minutes) where the sample is heated by about 500 Watt of
power (e.g., including from about 480 Watt to about 520 Watt) for
about 2 min (e.g., including about 30 seconds to about 5 minutes,
about 1 minute to about 5 minutes, about 5 minutes to about 20
minutes) and then heating can be turned off for about 1 min (e.g.,
including from about 30 seconds to about 5 minutes) before
repeating the heating at 500 Watt. The resulting nanowires 74 on
the inside and outside surfaces of a frustule 70 using the
above-described process are shown in FIGS. 5I and 5J. FIG. 5I shows
a SEM image, at 50 k.times. magnification, of ZnO nanowires 74
formed on both inside surfaces and outside surfaces of a diatom
frustule 70. In some embodiments, ZnO nanowires 74 can be formed on
a portion of a surface on an interior of a diatom frustule 70. For
example, ZnO nanowires 74 may be formed on all or substantially all
surfaces on an interior of a diatom frustule 70. ZnO nanowires 74
may be formed on all or substantially all interior and exterior
surfaces of a diatom frustule 70. The drawings of this application
provide proof that growth of nanostructures (e.g., ZnO nanowires)
on diatom frustules is possible, including growth of nanostructures
(e.g., ZnO nanowires) on the inside of diatom frustules. Coating
all or substantially all sides of the diatom frustules with ZnO
nanostructures may provide increased conductivity of a material
(e.g., ink or a layer printed therefrom) comprising the ZnO
nanostructure-coated diatom frustules (e.g., an increased bulk
conductivity and/or sheet conductivity), for example in comparison
to materials (e.g., ink or a layer printed therefrom) comprising
ZnO nanostructures formed only on the outside of a substrate. FIG.
5J shows a SEM image, at 25 k.times. magnification, of ZnO
nanowires 74 formed on surfaces of a diatom frustule 70. FIGS. 5M
and 5N are additional SEM images of diatom frustule 70 having ZnO
nanowires 74 on one or more surfaces. FIG. 5M is a SEM image of
diatom frustule 70 at 10 k.times. magnification. FIG. 5N is a SEM
image of diatom frustule 70 at 100 k.times. magnification. The
polyhedral, polygonal cross-section, and rod-like structure of the
ZnO nanowires 74 and their attachment to the surface of the
frustule 70 can be more clearly seen in FIG. 5N. When the heating
was performed in a microwave at 100 Watt (e.g., including from
about 80 Watt to about 120 Watt; and at about 2 min on, then about
1 min off, and repeated for a total duration of about 10 min),
nanoplates 76 can be formed on a surface of the frustules 70 (e.g.,
as shown in FIG. 5K).
In some embodiments, a process for forming ZnO nanostructures on
one or more surfaces of frustules seeded with ZnO comprises forming
a mixture comprising the following composition: about 1 weight % to
about 5 weight % seeded frustules, about 6 weight % to about 10
weight % zinc salt (e.g., Zn(NO.sub.3).sub.2), about 1 weight % to
about 2 weight % of a base (e.g., ammonium hydroxide (NH.sub.4OH)),
about 1 weight % to about 5 weight % of an additive (e.g.,
hexamethylenetetramine (HMTA)), and about 78 weight % to about 91
weight % purified water. In some embodiments, forming the ZnO
nanostructures comprises heating the mixture. The mixture may be
heated using microwave. For example, the mixture may be heated in a
microwave device to a temperature of about 100.degree. C. to about
250.degree. C. for about 30 minutes (min) to about 60 min (e.g., in
a Monowave 300 for a smaller scale synthesis, such as for a mixture
about 10 mL to about 30 mL, or a Masterwave BTR for a larger scale
synthesis, such as for about a 1 liter (L) mixture, both
commercially available from Anton Paar.RTM. GmbH). In some
embodiments, the mixture may be stirred while being heated by the
microwave. For example, the mixture may be stirred during heating
by a magnetic stirrer at about 200 rotations per minute (RPM) to
about 1000 RPM. Use of microwave heating may advantageously
facilitate reduced duration of heating, providing a more efficient
fabrication process.
In some embodiments, a frustule comprising ZnO nanostructures
formed thereon comprises about 5 weight % to about 95 weight % of
the ZnO, including about 10 weight % to about 95 weight %, about 20
weight % to about 95 weight %, about 30 weight % to about 95 weight
%, about 40 weight % to about 95 weight %, or about 50 weight % to
about 95 weight %, the remaining mass being the frustule. In some
embodiments, a frustule comprising ZnO nanostructures formed
thereon comprises about 5 weight % to about 95 weight % of the
frustule, the remaining mass being the ZnO. In some embodiments, a
frustule comprising ZnO nanostructures formed thereon comprises
about 40 weight % to about 50 weight % of the frustule, the
remaining mass being the ZnO. In some embodiments, a frustule
comprising ZnO nanostructures formed thereon comprises about 50
weight % to about 60 weight % of the ZnO, the remaining mass being
the ZnO. In some embodiments, a mass of the ZnO to a mass of the
frustule can be about 1:20 to about 20:1, including about 1:15 to
about 20:1, about 1:10 to about 20:1, about 1:1 to about 20:1,
about 2:1 to about 10:1, or about 2:1 to about 9:1. The ZnO
nanostructures preferably have a mass greater than a mass of the
frustules prior to coating. In some embodiments, the mass of the
ZnO nanostructures to the mass of the frustule can be greater than
about 1:1, about 10:1, or about 20:1. In certain such embodiments,
an upper limit may be based on, for example, openness of pores of
the frustules (e.g., ZnO nanostructures not completely occluding
the pores).
In some embodiments, a mass of the ZnO to a mass of the frustule
can be about 1:20 to about 100:1, including about 1:1 to about
100:1, about 10:1 to about 100:1, about 20:1 to about 100:1, about
40:1 to about 100:1, about 60:1 to about 100:1, or about 80:1 to
about 100:1. In some embodiments, the mass of the ZnO
nanostructures to the mass of the frustule can be greater than
about 30:1, about 40:1, about 50:1, about 60:1, about 70:1, about
80:1 or about 90:1. In some embodiments, a mass of the ZnO
nanostructures to a mass of the frustule can be selected to provide
desired device performance.
In some embodiments, pores of the frustules may be occluded by the
nanostructures. For example, ZnO nanostructures may be formed on
surfaces of the frustules, including surfaces within pores of the
frustules, such that the ZnO nanostructures may occlude or
substantially occlude some or all of the pores of the
frustules.
The mass of the ZnO nanostructures may be determined by weighing
the frustules before and after coating with the difference being
the mass of the ZnO nanostructures. In some embodiments, the
composition of the mixture for forming ZnO nanostructures can be
selected such that ZnO covered frustules comprising a desired ZnO
weight % can be formed. In some embodiments, the weight % of ZnO on
frustule surfaces can be selected based on a desired mass of
surface active material on an opposing energy storage device
electrode. For example, the composition of the mixture for forming
the ZnO nanostructures can be selected based on the mass of an
oxide of manganese in an opposing energy storage electrode, such as
the mass of one or more of MnO, Mn.sub.2O.sub.3, Mn.sub.3O.sub.4
and MnOOH. For example, based on stoichiometric calculations, a
mass of Mn.sub.203 in an energy storage device electrode can be at
least about 2.5 times that of ZnO in an opposing electrode.
Referring to FIG. 5O, a SEM image at 500.times. magnification of a
plurality of frustules 70 having ZnO nanostructures formed thereon
is shown. The frustules 70 covered with ZnO nanostructures were
first seeded with ZnO using a mixture consisting essentially of
about 2 weight % to about 5 weight % frustules, about 0.1 weight %
to about 0.5 weight % Zn(CH.sub.3COO).sub.2, and about 94.5 weight
% to about 97.9 weight % ethanol. The mixture for forming ZnO
seeded frustules was heated to a temperature greater than about
80.degree. C. for a duration to form the ZnO seeded frustules and
achieve desired drying of the ZnO seeded frustules. Subsequently,
ZnO nanostructures were formed on the ZnO seeded frustules using a
mixture consisting essentially of about 1 weight % to about 5
weight % ZnO seeded frustules, about 6 weight % to about 10 weight
% Zn(NO.sub.3).sub.2, about 1 weight % to about 2 weight % ammonium
hydroxide (NH.sub.4OH), about 1 weight % to about 5 weight %
hexamethylenetetramine (HMTA), and about 78 weight % to about 91
weight % purified water. The mixture was heated using microwave to
a temperature of about 100.degree. C. to about 250.degree. C. for
about 30 minutes (min) to about 60 min to facilitate formation of
the ZnO nanostructures and drying of the frustules. As shown in
FIG. 5O, unexpectedly, the plurality of frustules 70 having ZnO
nanostructures formed thereon did not or substantially did not
agglomerate. Each frustule 70 was individually covered or
substantially covered by ZnO nanostructures. Each of the frustules
70 having ZnO nanostructures formed thereon shown in FIG. 5O
included about 50% to about 60% by weight of ZnO. FIG. 5P shows a
SEM image at 5 k.times. magnification of an individual frustule 70
having ZnO nanostructures formed thereon. The ZnO nanostructures on
the frustule 70 of FIG. 5P were formed using the process described
with reference to FIG. 5O. As shown in FIG. 5P, the frustule 70 is
covered by ZnO nanoflakes 78. As shown in FIG. 5P, the frustule 70
comprising ZnO nanoflakes 78 formed thereon is porous. For example,
the ZnO nanoflakes 78 did not occlude pores of the frustules 70,
advantageously facilitating transport of electrolyte through an
electrode comprising the frustules 70 having the ZnO nanoflakes 78
formed thereon.
Examples of suitable Zn salts which can be used for both ZnO
seeding and nanostructures growth include: zinc acetate hydrate,
zinc nitrate hexahydrate, zinc chloride, zinc sulfate, sodium
zincate, combinations thereof, and/or the like.
Examples of suitable bases for ZnO nanostructures growth may
include: sodium hydroxide, ammonium hydroxide, potassium hydroxide,
tetramethylammonium hydroxide, lithium hydroxide,
hexamethylenetetramine, ammonia solutions, sodium carbonate,
ethylenediamine, combinations thereof, and/or the like.
Examples of suitable solvents for formation of ZnO nanostructures
include one or more alcohols. Solvents described herein as being
suitable for Ag nanostructures growth may also be suitable for ZnO
nanostructure formation.
Examples of additives that may be used for nanostructures
morphology control may include tributylamine, triethylamine,
triethanolamine, diisopropylamine, ammonium phosphate,
1,6-hexadianol, triethyldiethylnol, isopropylamine,
cyclohexylamine, n-butylamine, ammonium chloride,
hexamethylenetetramine, ethylene glycol, ethanolamine,
polyvinylalcohol, polyethylene glycol, sodium dodecyl sulphate,
cetyltrimethyl ammonium bromide, carbamide, combinations thereof,
and/or the like.
Example Process of Forming Carbon Nanotubes on a Surface of a
Diatom Frustule
Carbon nanotubes (e.g., multiwall and/or single-wall) can be grown
on a diatom surface (e.g., inside and/or outside) by chemical vapor
deposition technique and its varieties. In this technique, the
diatoms are firstly coated with catalyst seeds and then a mixture
of gases is introduced. One of the gases may be a reducing gas and
another gas may be a source of carbon. In some embodiments, a
mixture of gases may be used. In some embodiments, a neutral gas
can be included for the concentration control (e.g., argon). Argon
may also be used to carry liquid carbonaceous material (e.g.,
ethanol). The seeds for forming a carbon nanotube can be deposited
as metals by such techniques as spray coating and/or introduced
from a liquid, a gas, and/or a solid and reduced later under
elevated temperatures by pyrolysis. The reduction of carbonaceous
gases may occur at higher temperatures, for example in a range of
about 600.degree. C. to about 1100.degree. C.
Both the seed coating process and gas reactions can be realized on
frustules surfaces due to nanoporosity. Techniques have been
developed for carbon nanotubes "forest" growth on different
substrates including silicon, alumina, magnesium oxide, quartz,
graphite, silicon carbide, zeolite, metals, and silica.
Examples of suitable metal compounds for growth of catalyst seeds
can include nickel, iron, cobalt, cobalt-molybdenum bimetallic
particles, copper (Cu), gold (Au), Ag, platinum (Pt), palladium
(Pd), manganese (Mn), aluminum (Al), magnesium (Mg), chromium (Cr),
antimony(Sn), aluminum-iron-molybdenum (Al/Fe/Mo), Iron
pentacarbonyl (Fe(CO).sub.5), iron (III) nitrate hexahydrate
(Fe(NO.sub.3).sub.3.6H.sub.2O), iron (III) nitrate hexahydrate
(COCl.sub.2.6H.sub.2O) ammonium molybdate tetrahydrate
((NH.sub.4).sub.6Mo.sub.7O.sub.24.4H.sub.2O), ammonium molybdate
tetrahydrate ((NH.sub.4).sub.6Mo.sub.7O.sub.24.4H.sub.2O)
(MoO.sub.2Cl.sub.2) alumina nanopowder, mixtures thereof, and/or
the like.
Examples of suitable reducing gases may include ammonia, nitrogen,
hydrogen, mixtures thereof, and/or the like.
Examples of suitable gases which may serve as a source of carbon
(e.g., carbonaceous gases) may include acetylene, ethylene,
ethanol, methane, carbon oxide, benzene, mixtures thereof, and/or
the like.
Example Processes of Forming Manganese-Containing Nanostructures on
Surfaces of Diatom Frustules
In some embodiments, manganese-containing nanostructures can be
formed on one or more surfaces of a frustule. In some embodiments,
an oxide of manganese can be formed on one or more surfaces of a
frustule. In some embodiments, nanostructures comprising oxide of
manganese having the formula Mn.sub.xO.sub.y where x is about 1 to
about 3 and where y is about 1 to about 4, can be formed on one or
more surfaces of a frustule. For example, nanostructures comprising
manganese dioxide (MnO.sub.2), manganese (II, III) oxide
(Mn.sub.3O.sub.4), manganese (II) oxide (MnO), and/or manganese
(III) oxide (Mn.sub.2O.sub.3) can be formed on one or more surfaces
of a frustule. In some embodiments, nanostructures comprising
manganese oxyhydroxide (MnOOH) can be formed on one or more
surfaces of a frustule. In some embodiments, a membrane of an
energy storage device can include frustules having
manganese-containing nanostructures. In some embodiments, a printed
energy storage device (e.g., a battery, a capacitor, a
supercapacitor, and/or a fuel cell) can include one or more
electrodes having a plurality of frustules which comprise
manganese-containing nanostructures. In some embodiments, an ink
used for printing a film can comprise a solution in which frustules
comprising manganese-containing nanostructures are dispersed.
In some embodiments, one or more electrodes of a battery can
include frustules comprising manganese-containing nanostructures on
one or more surfaces (e.g., an electrode of a zinc-manganese
battery). A charged battery can include a first electrode including
frustules comprising nanostructures comprising manganese dioxide
(MnO.sub.2) and a second electrode comprising zinc (e.g., frustules
comprising a zinc coating). In some embodiments, the second
electrode can comprise other materials. A discharged battery can
include a first electrode including frustules comprising
nanostructures comprising manganese (II, III) oxide
(Mn.sub.3O.sub.4), manganese (II) oxide (MnO), manganese (III)
oxide (Mn.sub.2O.sub.3), and/or manganese oxyhydroxide (MnOOH) and
a second electrode including zinc oxide (ZnO) (e.g., frustules
comprising nanostructures comprising zinc oxide). In some
embodiments, the second electrode of the discharged battery can
comprise other materials. In some embodiments, a charged battery
can include a first electrode comprising frustules having manganese
(II, III) oxide (Mn.sub.3O.sub.4), manganese (II) oxide (MnO),
manganese (III) oxide (Mn.sub.2O.sub.3), and/or manganese
oxyhydroxide (MnOOH) nanostructures formed thereon and a second
opposing electrode comprising ZnO nanostructures formed thereon. In
some embodiments, the battery can be a rechargeable battery.
A method of forming manganese-containing nanostructures on a diatom
frustule portion can include adding the frustules to an oxygenated
manganese acetate solution, and heating the frustules and the
oxygenated manganese acetate solution. An example of a process for
forming Mn.sub.3O.sub.4 on one or more surfaces of a frustule is
provided. For example, pure water (e.g., pure water commercially
available from EMD Millipore Corporation, of Billerica, Mass.) can
be bubbled with oxygen gas (O.sub.2) for a duration of about 10
minutes (min) to about 60 min (e.g., O.sub.2 purging) to form
oxygenated water. Manganese(II) acetate (Mn(CH.sub.3COO).sub.2) can
then be dissolved in the oxygenated water at a concentration of
about 0.05 moles/liter (M) to about 1.2 M to form an oxygenated
manganese acetate solution.
Frustules can be added to the oxygenated manganese acetate
solution. Frustules added to the oxygenated manganese acetate
solution may not have any previously formed nanostructures and/or
coatings on frustule surfaces. In some embodiments, frustules added
to the oxygenated manganese acetate solution can have one or more
nanostructures and/or coatings on frustule surfaces. In some
embodiments, frustules added to the oxygenated manganese acetate
solution can have one or more nanostructures and/or coatings on at
least some portions of the frustule surfaces. For example,
frustules may have carbon-containing nanostructures on portions of
frustule surfaces such that manganese-containing nanostructures
formed according to one or more processes as described herein can
be interspersed amongst the carbon-containing nanostructures. In
some embodiments, carbon-containing nanostructures can include
reduced graphene oxide, carbon nanotubes (e.g., single wall and/or
multi-wall), and/or carbon nano-onions. Carbon-containing
nanostructures can be formed on frustule surfaces according to one
or more processes as described herein or other processes.
In some embodiments, frustules can be added to the oxygenated
manganese acetate solution such that the solution comprises about
0.01 weight % to about 1 weight % of frustules. In some
embodiments, other Mn.sup.2+ salts can be suitable. In some
embodiments, other oxidizing agents (e.g., peroxides) can be
suitable.
In some embodiments, growth of manganese-containing nanostructures
can be conducted using a thermal technique and/or a microwave
technique. In some embodiments, desired growth of nanostructures
can involve a longer duration when using a thermal method. For
example, a thermal technique may include using thermal heating in
the nanostructure growth process. An example of a thermal method of
growing nanostructures may include mixing (e.g., by stirring using
any number of suitable techniques) frustules in the oxygenated
manganese acetate solution for a duration of about 15 hours to
about 40 hours (e.g., about 24 hours), while maintaining the
mixture at a temperature of about 50 degrees C. (.degree. C.) to
about 90.degree. C. (e.g., at about 60.degree. C.). In some
embodiments, the temperature of the mixture can be maintained by
thermally heating the mixture.
In some embodiments, a microwave method of growing nanostructures
can facilitate a shorter nanostructure growth process and/or
facilitate a scalable nanostructure growth process. For example, a
microwave method of nanostructure growth may include using
microwave heating in the nanostructure growth process. An example
of a nanostructure growth process using the microwave technique may
include adding frustules to the oxygenated manganese acetate
solution, and maintaining the mixture at a temperature of about
50.degree. C. to about 150.degree. C. for about 10 minutes (min) to
about 120 min. The mixture may be stirred while it is being
maintained at the temperature.
In some embodiments, manganese-containing structures having a
reddish-brown color (e.g., after washing and drying) can form on
one or more surfaces of frustules using one or more processes
described herein. In some embodiments, the manganese oxide
structures can have a tetrahedral shape. A reddish-brown color may
indicate presence of manganese(II, III) oxide (Mn.sub.3O.sub.4). In
some embodiments, formation of tetrahedral nanocrystals can
indicate presence of manganese(II, III) oxide
(Mn.sub.3O.sub.4).
FIG. 5Q is a scanning electron microscope (SEM) image at 20
k.times. magnification of an example of a frustule 80 having
nanostructures comprising manganese(II, III) oxide
(Mn.sub.3O.sub.4) 82 on or more of its surfaces, where the
nanostructures 82 are formed using a microwave method of
nanostructure growth. FIG. 5R is a SEM image at 50 k.times.
magnification of the frustule 80 shown in FIG. 5Q. The
nanostructures 82 comprising manganese(II, III) oxide
(Mn.sub.3O.sub.4) shown in FIGS. 5Q and 5R can be formed by using
an oxygenated solution having a concentration of about 0.15 M
manganese acetate prepared by bubbling oxygen gas (O.sub.2) through
pure water for a duration of about 30 min. For example, commercial
grade oxygen gas (e.g., purity level of greater than 95%, such as
at least about 97% pure, or at least about 99% pure) can be used.
For example, oxygen gas having a purity of at least about 97% can
be bubbled through a glass frit into a vial (e.g., a vial having a
volume of about 20 milliliter (mL)) containing about 15 mL of pure
water for a duration of about 30 minutes at room temperature (e.g.,
at about 25.degree. C.). A weight of 0.55 grams (g) of manganese
acetate tetrahydrate (e.g., commercially available from
Sigma-Aldrich Corp.) can be dissolved in the oxygenated pure water.
A weight of 0.005 grams (g) of diatoms can be added to the
oxygenated manganese-containing solution. Then the vial containing
the mixture comprising the added frustules can be placed in a
microwave (e.g., Monowave 300 microwave, commercially available
from Anton Paar.RTM. GmbH), and the synthesis can be conducted at a
desired temperature for a desired period of time. The mixture
comprising the solution and frustules can be maintained for about
30 minutes at a temperature of about 60.degree. C., for example
under continues stirring (e.g., with a magnetic stir bar, such as
at a rotation speed of about 600 rpm). In some embodiments, the
mixture can be subsequently diluted with water, and centrifuged
(e.g., at about 5000 rpm for about 5 min) such that the supernatant
can be discarded. In some embodiments, the precipitate can be
diluted with water again, then dispersed (e.g., shaking, and/or
vortexing) and again centrifuged such that the supernatant can be
discarded. The precipitate can then be dried at about 70.degree. C.
to about 80.degree. C. in a vacuum oven.
Referring to FIG. 5R, the nanostructures 82 can have a tetrahedral
shape. It was observed that the manganese(II, III) oxide
(Mn.sub.3O.sub.4) structures surprisingly grow on the surface of
the frustules rather than forming in the solution separate from
frustules.
FIG. 5S is a transmission electron microscope (TEM) image of
nanostructures 82 formed on surfaces of the frustule shown in FIGS.
5Q and 512. One or more individual atoms of the nanostructures 82
can be seen, and a scale is provided for size comparison. FIG. 5T
shows an electron diffraction image of a manganese(II, III) oxide
(Mn.sub.3O.sub.4) particle.
In some embodiments, a shape and/or dimension of nanostructures
formed on a frustule surface can depend on a parameter of the
nanostructure formation process. For example, morphology of
nanostructures can depend on a solution concentration and/or a
level of oxygenation of the solution. FIG. 5U is a SEM image at 10
k.times. magnification of a frustule 90 comprising
manganese-containing nanostructures 92 formed on its surfaces,
where the manganese-containing nanostructures 92 were formed using
a solution having a higher oxygen concentration (e.g., oxygen
purging of water for a duration of about 40 minutes) and higher
manganese concentration (e.g., a manganese acetate concentration of
about 1 M), as compared to the process used in the formation of
nanostructures 82 shown in FIGS. 5Q and 5R. For example, the
nanostructures 92 can be formed on frustules 90 according to the
process as described with reference to formation of nanostructures
82 (e.g., of FIGS. 5Q and 5R), except with the following
differences: oxygen gas bubbling of the pure water can be performed
for a duration of about 40 minutes, with the addition of about 0.9
grams (g) of manganese acetate to the oxygenated pure water, and
about 0.01 grams (g) of diatoms can be added to the
manganese-containing solution, and the mixture comprising the
diatoms and manganese-containing solution can be microwaved at a
temperature of about 150.degree. C.
As shown in FIG. 5U, the nanostructures 92 can have an elongate
fiber-like shape. In some embodiments, the nanostructures 92 can
have a thin elongate shape (e.g., thin whisker-like structure). In
some embodiments, formation of fiber-like structures can indicate
presence of manganese oxyhydroxide (MnOOH).
In some embodiments, forming nanostructures comprising one or more
oxides of manganese having the formula Mn.sub.xO.sub.y where x is
about 1 to about 3 and where y is about 1 to about 4, on one or
more surfaces of a frustule can include combining frustules with a
manganese source, such as a manganese salt (e.g., manganese acetate
(Mn(CH.sub.3COO).sub.2)) and a base (e.g., ammonium hydroxide
(NH.sub.4OH)) in oxygenated water. In some embodiments, forming the
Mn.sub.xO.sub.y nanostructures on one or more surfaces of frustules
can include forming a mixture comprising the following composition:
about 0.5 weight % to about 2 weight % of frustules, about 7 weight
% to about 10 weight % of Mn(CH.sub.3COO).sub.2, about 5 weight %
to about 10 weight % of NH.sub.4OH and about 78 weight % to about
87.5 weight % of oxygenated purified water. In some embodiments,
oxygenated purified water for the mixture can be prepared by
bubbling oxygen through the purified water for about 10 minutes to
about 30 minutes. The mixture may be heated using microwave to
facilitate formation of the Mn.sub.xO.sub.y nanostructures (e.g.,
in a Monowave 300 for a smaller scale synthesis, such as for a
mixture about 10 mL to about 30 mL, or a Masterwave BTR for a
larger scale synthesis, such as for about a 1 liter (L) mixture,
both commercially available from Anton Paar.RTM. GmbH). For
example, the mixture may be heated using a microwave to a
temperature of about 100.degree. C. to about 250.degree. C. for
about 30 minutes to about 60 minutes. In some embodiments, the
mixture can be stirred while being heated, for example by a
magnetic stirrer at about 200 rotations per minute (RPM) to about
1000 RPM.
In some embodiments, a frustule comprising an oxide of manganese
(e.g., an oxide having the formula Mn.sub.xO.sub.y where x is about
1 to about 3 and y is about 1 to about 4) nanostructures formed
thereon comprises about 5 weight % to about 95 weight % of the
oxide of manganese, including about 30 weight % to about 95 weight
%, about 40 weight % to about 95 weight %, about 40 weight % to
about 85 weight %, about 50 weight % to about 85 weight %, about 55
weight % to about 95 weight %, or about 75 weight % to about 95
weight %, the remaining mass being the frustule. In some
embodiments, a frustule comprising an oxide of manganese (e.g., an
oxide having the formula Mn.sub.xO.sub.y where x is about 1 to
about 3 and y is about 1 to about 4) nanostructures formed thereon
comprises about 5 weight % to about 50 weight % of the frustule,
the remaining mass being the oxide of manganese nanostructures. In
some embodiments, a mass of the oxide of manganese nanostructures
to a mass of the frustule can be about 1:20 to about 20:1,
including about 1:15 to about 20:1, about 1:10 to about 20:1, about
1:1 to about 20:1, about 5:1 to about 20:1, about 1:1 to about
10:1, or about 2:1 to about 9:1. The oxide of manganese
nanostructures preferably have a mass greater than a mass of the
frustules prior to coating. In some embodiments, a ratio of the
mass of the oxide of manganese nanostructures to the mass of the
frustule can be greater than about 1:1, about 10:1, or about 20:1.
In certain such embodiments, an upper limit may be based on, for
example, openness of pores of the frustules (e.g., the oxide of
manganese nanostructures not completely occluding the pores).
In some embodiments, pores of the frustules may be occluded by the
nanostructures. For example, oxide of manganese nanostructures may
be formed on surfaces of the frustules, including surfaces within
pores of the frustules, such that the oxide of manganese
nanostructures may occlude or substantially occlude some or all of
the pores of the frustules.
In some embodiments, a mass of the oxide of manganese
nanostructures to a mass of the frustule can be about 1:20 to about
100:1, including about 1:1 to about 100:1, about 10:1 to about
100:1, about 20:1 to about 100:1, about 40:1 to about 100:1, about
60:1 to about 100:1, or about 80:1 to about 100:1. In some
embodiments, the mass of the manganese nanostructures to the mass
of the frustule can be greater than about 30:1, about 40:1, about
50:1, about 60:1, about 70:1, about 80:1 or about 90:1. In some
embodiments, a mass of the manganese nanostructures to a mass of
the frustule can be selected to provide desired device
performance.
The mass of the oxide of manganese nanostructures may be determined
by weighing the frustules before and after coating with the
difference being the mass of the oxide of manganese nanostructures.
In some embodiments, the composition of the mixture for forming
oxide of manganese nanostructures can be selected such that a
desired oxide of manganese weight % can be formed. In some
embodiments, the weight % of the oxide of manganese on frustule
surfaces can be selected based on a desired mass of surface active
material on an opposing energy storage device electrode. For
example, the composition of the mixture for forming the oxide of
manganese nanostructures can be selected based on the mass of ZnO
in an opposing energy storage device electrode. In some embodiment,
based on stoichiometric calculations, a mass of Mn.sub.2O.sub.3 in
an energy storage device electrode can be at least about 2.5 times
that of ZnO in an opposing electrode.
FIG. 5V is a SEM image at 20 k.times. magnification of a frustule
94 comprising oxides of manganese nanostructures 96 formed thereon.
The nanostructures 96 included a mixture of different oxides of
manganese, the oxides having the formula Mn.sub.xO.sub.y where x is
about 1 to about 3 and y is about 1 to about 4. As shown in FIG.
5V, the frustule 94 is thickly covered by the oxide of manganese
nanostructures 96. FIG. 5W is a SEM image at 50 k.times.
magnification of a cross-sectional view of a frustule 94 comprising
oxides of manganese nanostructures 96 (e.g., oxides having the
formula Mn.sub.xO.sub.y where x is about 1 to about 3 and y is
about 1 to about 4) formed thereon. The frustule 94 was cut using
focused ion beam (FIB) technique and a cross-section view of the
cut frustule 94 is shown in FIG. 5W. As shown in FIG. 5W, the
oxides of manganese nanostructures 96 can be formed on interior and
exterior surfaces of the frustule 94, and a volume of the
nanostructures 96 can be greater than a volume of the frustule 94.
FIG. 5X is a SEM image at 100 k.times. magnification of a sidewall
of a frustule 94 comprising oxides of manganese nanostructures 96
(e.g., oxides having the formula Mn.sub.xO.sub.y where x is about 1
to about 3 and y is about 1 to about 4) formed thereon. As shown in
FIG. 5X, a sidewall of the frustule 94 can be covered by the oxides
of manganese nanostructures 96 while pores on the sidewall are not
occluded. A frustule having oxide of manganese nanostructures
formed thereon without or substantially without occluding pores of
the frustule can advantageously facilitate transport of electrolyte
through an electrode comprising the frustule covered by the oxide
of manganese nanostructures.
The frustules 94 comprising the oxides of manganese nanostructures
96 formed thereon shown in FIGS. 5V through 5X were formed using a
mixture consisting essentially of about 0.5 weight % to about 2
weight % of frustules, about 7 weight % to about 10 weight % of
Mn(CH.sub.3COO).sub.2, about 5 weight % to about 10 weight % of
NH.sub.4OH and about 78 weight % to about 87.5 weight % of
oxygenated purified water. The mixture was heated using microwave
to a temperature of about 100.degree. C. to about 250.degree. C.
for about 30 minutes to about 60 minutes. As shown in FIGS. 5V
through 5X, the frustules 94 were thickly covered by the oxides of
manganese nanostructures 96. For example, about 75 weight % to
about 95% of oxides of manganese nanostructure covered frustule was
the nanostructures and the remaining mass was the mass of the
frustule.
Combination of Coatings
In some embodiments, a combination of coating can also be possible.
For example, a surface of a frustule may include both a nickel
coating and a coating of carbon nanotubes (e.g., such a frustule
can be used for energy storage devices, including
supercapacitors).
FIG. 6 schematically illustrates an example embodiment of an energy
storage device 100. FIG. 6 may be a cross-section or elevational
view of the energy storage device 100. The energy storage device
100 includes a first electrode 140 and a second electrode 150, for
example a cathode and an anode, respectively or irrespectively. The
first and second electrodes 140, 150 are separated by a separator
130. The energy storage device 100 may optionally include one or
more current collectors 110, 120 electrically coupled to one or
both of the electrodes 140, 150.
In some embodiments, the energy storage device 100 comprises a
first electrode 140, a second electrode 150, and/or a separator
130, any of which may be a membrane or layer, including a deposited
membrane or layer.
A current collector 110, 120 may include any component that
provides a path for electrons to external wiring. For example, a
current collector 110, 120 may be positioned adjacent to the
surface of the first and second electrodes 140, 150 to allow energy
flow between the electrodes 140, 150 to be transferred to an
electrical device. In the embodiment shown in FIG. 6, a first
current collector layer 110 and a second collector layer 120 are
adjacent to the surface of the first electrode 140 and to the
surface of the second electrode 150, respectively. The current
collectors 110, 120 are adjacent to surfaces opposite to surfaces
of the electrode 140, 150, respectively, that are adjacent to the
separator layer 130.
In some embodiments, the current collector 110, 120 comprises an
electrically conductive foil (e.g., graphite, such as graphite
paper, graphene, such as graphene paper, aluminum (Al), copper
(Cu), stainless steel (SS), carbon foam). In some embodiments, the
current collector 110, 120 comprises an electrically conductive
material deposited on a substrate. For example, the current
collector 110, 120 can comprise an electrically conductive material
printed on a substrate. In some embodiments, a suitable substrate
can include polyester, polyimide, polycarbonate, cellulose (e.g.,
cardboard, paper, including coated paper, such as plastic coated
paper, and/or fiber paper). In some embodiments, the conductive
material can comprise silver (Ag), copper (Cu), carbon (C) (e.g.,
carbon nanotubes, graphene, and/or graphite), aluminum (Al), nickel
(Ni), combinations thereof, and/or the like. Examples of a
conductive material comprising nickel suitable for current
collectors are provided in PCT Patent Application No.
PCT/US2013/078059, entitled "NICKEL INKS AND OXIDATION RESISTANT
AND CONDUCTIVE COATINGS," filed Dec. 27, 2013, which is
incorporated herein by reference in its entirety.
In some embodiments, an energy storage device 100 includes at least
one layer or membrane comprising frustules. For example, an energy
storage device 100 may include a layer or membrane comprising a
dispersion including frustules. The layer or membrane comprising
frustules may include, for example, the first electrode 140, the
second electrode 150, the separator 130, the first collector layer
110, the second collector layer 120, combinations thereof, and/or
the like. In some embodiments, the energy storage device 100
includes frustules having a uniform or substantially uniform shape,
dimension (e.g., diameter, length), material, porosity, a surface
modifying material and/or structure, any other suitable feature or
attribute, combinations thereof, and/or the like. In embodiments in
which a plurality of layers of the energy storage 100 device
comprise frustules, the frustules may be the same or substantially
the same (e.g., having similar dimensions) or may be different
(e.g., insulating in the separator 130 and conductively coated in
an electrode 140, 150).
The energy storage device 100 may include one or more layers or
membranes comprising frustules having a length in a range from
about 0.5 .mu.m to about 50 .mu.m, from about 1 .mu.m to about 50
.mu.m, from about 1 .mu.m to about 40 .mu.m, from about 1 .mu.m to
about 30 .mu.m, from about 1 .mu.m to about 20 .mu.m, from about 1
.mu.m to about 10 .mu.m, from about 5 .mu.m to about 50 .mu.m, from
about 5 .mu.m to about 40 .mu.m, from about 5 .mu.m to about 30
.mu.m, from about 5 .mu.m to about 20 .mu.m, and from about 5 .mu.m
to about 10 .mu.m. In some embodiments, the cylindrically shaped
frustules have a length of no more than about 50 .mu.m, no more
than about 40 .mu.m, no more than about 30 .mu.m, no more than
about 20 .mu.m, no more than about 15 .mu.m, no more than about 10
.mu.m, or no more than about 5 .mu.m. Other frustule lengths are
also possible.
The energy storage device 100 may comprise one or more layers or
membranes comprising frustules having diameters within a range of
from about 0.5 .mu.m to about 50 .mu.m, from about 1 .mu.m to about
50 .mu.m, from about 1 .mu.m to about 40 .mu.m, from about 1 .mu.m
to about 30 .mu.m, from about 1 .mu.m to about 20 .mu.m, from about
1 .mu.m to about 10 .mu.m, from about 5 .mu.m to about 50 .mu.m,
from about 5 .mu.m to about 40 .mu.m, from about 5 .mu.m to about
30 .mu.m, from about 5 .mu.m to about 20 .mu.m, and from about 5
.mu.m to about 10 .mu.m. In some embodiments, the cylindrically
shaped frustules have a diameter of no more than about 50 .mu.m, no
more than about 40 .mu.m, no more than about 30 .mu.m, no more than
about 20 .mu.m, no more than about 15 .mu.m, no more than about 10
.mu.m, no more than about 5 .mu.m, no more than about 2 .mu.m, or
no more than about 1 .mu.m. Other frustule diameters are also
possible.
The energy storage device 100 may comprise frustules having a
uniform or substantially uniform within-frustule porosity and/or
frustule-to-frustule porosity and/or frustules having porosity
within a particular range. In some embodiments, the energy storage
device 100 comprises one or more layers or membranes including
frustules having porosities in a range of from about 10% to about
50%, from about 15% to about 45%, and from about 20% to about 40%.
In some embodiments, pores on frustule surfaces can have a size
(e.g., a length, width, diameter, and/or longest dimension) of
about 1 nanometer (nm) to about 500 nm. For example, pores on a
frustule surface can have a size that can facilitate desired energy
storage device performance (e.g., diffusion of electrolytic ions of
the energy storage device to facilitate a desired electrical
performance of the device). Other frustule porosities are also
possible.
As described herein, an energy storage device 100 may include one
or more layers or membranes including frustules 50 comprising no or
substantially no surface modifying material and/or surface
modifying structures 52 applied or formed on a surface of the
frustules 50 and/or frustules 50 comprising a material and/or
structures 52 applied or formed on a surface of the frustules 50 to
modify a characteristic or attribute of the frustules 50. For
example, the separator 130 may comprise frustules 50 comprising no
or substantially no surface modifying material and/or surface
modifying structures 52 applied or formed on a surface of the
frustules 50, and at least one of the electrodes 140, 150 may
comprise frustules 50 comprising a material and/or structures 52
applied or formed on a surface of the frustules 50 to modify a
characteristic or attribute of the frustules 50. For another
example, the separator 130 may comprise some frustules 50
comprising no or substantially no surface modifying material and/or
surface modifying structures 52 applied or formed on a surface of
the frustules 50 and some frustules 50 comprising a material and/or
structures 52 applied or formed on a surface of the frustules 50 to
modify a characteristic or attribute of the frustules 50.
In some embodiments, the energy storage device 100 comprises
frustules having a non-uniform or substantially non-uniform shape,
dimension, porosity, surface modifying material and/or structure,
another suitable attribute, and/or combinations thereof.
In some embodiments, one or more layers or membranes of the energy
storage device 100 may be printed. In some embodiments, one or more
layers or membranes of the energy storage device 100 can be printed
from an ink. In some embodiments, the ink can be printed using
various techniques described herein, including stenciling, screen
printing, rotary printing, die coating, rotogravure printing, flexo
and pad printing, combinations thereof, and/or the like. In some
embodiments, a viscosity of the ink can be adjusted based on the
printing technique applied (e.g., a desired viscosity may be
achieved by adjusting, for example, a quantity of the solvent used
for the ink).
In some embodiments, current collectors may be printed using a
conductive ink. For example, the current collector can comprise an
electrically conductive material printed on a substrate. In some
embodiments, a suitable substrate can include polyester, polyimide,
polycarbonate, cellulose (e.g., cardboard, paper, including coated
paper, such as plastic coated paper, and/or fiber paper). In some
embodiments, the conductive ink may comprise aluminum, silver,
copper, nickel, bismuth, conductive carbon, carbon nanotubes,
graphene, graphite, combinations thereof, and/or the like. In some
embodiments, the conductive material can comprise silver (Ag),
copper (Cu), carbon (C) (e.g., carbon nanotubes, graphene, and/or
graphite), aluminum (Al), nickel (Ni), combinations thereof, and/or
the like. Examples of a conductive material comprising nickel
suitable for current collectors are provided in PCT Patent
Application No. PCT/US2013/078059, entitled "NICKEL INKS AND
OXIDATION RESISTANT AND CONDUCTIVE COATINGS," filed Dec. 27, 2013,
which is incorporated herein by reference in its entirety.
In some embodiments, an ink can be prepared using a plurality of
frustules. The ink comprising the frustules may be printed to form
a component of an energy storage device, such as an electrode or a
separator of an energy storage device. In some embodiments, the ink
may comprise frustules comprising nanostructures formed thereon,
including one or more nanostructures described herein. For example,
an ink comprising nanostructure covered frustules may be printed to
form an electrode of the energy storage device 100. In some
embodiments, the ink may comprise frustules having no or
substantially no nanostructures formed thereon. For example, an ink
comprising frustules having no or substantially no surface
modifications may be printed to form the separator 130 of the
energy storage device 100.
FIGS. 7A through 7E are schematic diagrams showing cross-sectional
views of examples of energy storage devices. In some embodiments,
the energy storage devices of FIGS. 7A through 7E are printed
energy storage devices. For example, the energy storage devices of
FIGS. 7A through 7E may include a first current collector 110, a
second current collector 120, a first electrode 140, a second
electrode 150 and a separator 130, which are all printed. For
example, one or more layers of the printed energy storage devices
of FIGS. 7A through 7C can be printed on separate substrates and
the separate substrates can be subsequently assembled together to
form the energy storage device, while layers of the energy storage
devices of FIGS. 7D and 7E can be printed on one substrate.
In some embodiments, FIGS. 7A through 7C are schematic diagrams
showing cross-sectional views of examples of partially printed
energy storage devices, while FIGS. 7D and 7E are schematic
diagrams showing cross-sectional views of fully printed energy
storage devices, during various stages of the respective
manufacturing processes. The energy storage devices shown in FIGS.
7A through 7C may include current collectors 110, 120, which may be
printed (e.g., over separate substrates) and/or not printed (e.g.,
acting as a substrate on which other layers are printed). FIGS. 7D
and 7E show cross-sectional views of energy storage devices which
include current collectors 110, 120, which may be printed (e.g.,
each over a substrate) or not printed (e.g., the first current
collector 110 in FIG. 7D acting as a substrate on which other
layers are printed, the first and second current collectors 110,
120 acting together as a substrate on which other layers are
printed in FIG. 7E).
In some embodiments, the first current collector 110, second
current collector 120, first electrode 140, second electrode 150,
and/or separator 130 of FIGS. 7A through 7E can have one or more
properties and/or be fabricated as described herein. For example,
the first current collector 110, second current collector 120,
first electrode 140, second electrode 150, and/or separator 130 can
be printed using one or more techniques and/or ink compositions as
described herein. For example, one of the electrodes 140, 150 may
comprise frustules including nanostructures comprising an oxide of
manganese (e.g., oxide having the formula Mn.sub.xO.sub.y where x
is about 1 to about 3 and y is about 1 to about 4) and the other of
the electrodes 140, 150 may comprise frustules including
nanostructures comprising zinc (e.g., ZnO), one or both of which
may be printed from an ink. For another example, the separator 130
may comprise frustules comprising no or substantially no surface
modification, which may be printed from an ink. As described
herein, non-printed current collectors may comprise an electrically
conductive foil, such as a foil comprising aluminum, copper,
nickel, stainless steel, graphite (e.g., graphite paper), graphene
(e.g., graphene paper), carbon nanotubes, carbon foam, combinations
thereof, and the like. In some embodiments, the conductive foil can
be laminated and have a polymer layer on one of its two opposing
surfaces.
In FIG. 7A, an energy storage device 200 includes a first structure
202 and a second structure 204. The first structure 202 comprises a
first electrode 140 over a first current collector 110 and a
separator 130 over the first electrode 140. The second structure
204 comprises a second electrode 150 over a second current
collector 120. In some embodiments, the first electrode 140 can be
printed over the first current collector 110. For example, the
first electrode 140 can be printed directly on and in contact with
the first current collector 110. In some embodiments, the separator
130 can be printed over the first electrode 140. For example, the
separator 130 may be printed directly on and in contact with the
first electrode 140. In some embodiments, the separator 130 can be
printed over the first electrode 140 such that the separator 130
and the first current collector 110 encapsulate or substantially
encapsulate the first electrode 140. In some embodiments, the
second electrode 150 can be printed over the second current
collector 120, for example directly on and in contact with the
second current collector 120. In some embodiments, a process for
fabricating the energy storage device 200 can include assembling
together the first structure 202 and the second structure 204. For
example, fabricating the energy storage device 200 shown in FIG. 7A
can include bringing the second electrode 150 of the second
structure 204 into contact with the separator 130 of the first
structure 202 such that the separator 130 is between the first
electrode 140 and the second electrode 150.
FIG. 7B shows an energy storage device 210 comprising a first
structure 212 comprising a first electrode 140 over a first current
collector 110 and a first portion of a separator 130 over the first
electrode 140. The energy storage device 210 may comprise a second
structure 214 comprising a second electrode 150 over a second
current collector 120, and a second portion of the separator 130
over the second electrode 150. In some embodiments, the second
electrode 150 can be printed over the second current collector 120.
For example, the second electrode 150 can be printed on and in
direct contact with the second current collector 120. In some
embodiments, the second portion of the separator 130 can be printed
on and in direct contact with the second electrode 150. For
example, the second portion of the separator 130 can be printed on
and in direct contact with the second electrode 150. In some
embodiments, the first electrode 140 can be printed over the first
current collector 110. For example, the first electrode 140 can be
printed on and in direct contact with the first current collector
110. In some embodiments, the first portion of the separator 130
can be printed over the first electrode 140. For example, the first
portion of the separator 130 can be printed on and in direct
contact with the first electrode 140. In some embodiments, the
first and second portions of the separator 130 can be printed such
that the first portion of the separator 130 and the first current
collector 110 encapsulate or substantially encapsulate the first
electrode 140, and/or the second portion of the separator 130 and
the second current collector 120 encapsulate or substantially
encapsulate the second electrode 150. In some embodiments, a
process for fabricating the energy storage device 210 can include
assembling together (e.g., coupling) the first structure 212 and
the second structure 214 to form the energy storage device 210.
Assembling the first structure 212 and the second structure 214 may
comprise providing the first and second portions of the separator
130 between the first electrode 140 and the second electrode 150.
For example, fabricating the energy storage device 210 shown in
FIG. 7B can include bringing the second portion of the separator
130 of the second structure 214 into contact with the first portion
of the separator 130 of the first structure 212 such that the two
portions of the separator 130 are between the first electrode 140
and the second electrode 150.
As shown in FIG. 7C, in some embodiments, an energy storage device
220 may comprise a first structure 222 comprising a first electrode
140 over a first current collector 110, a separator 130 over the
first electrode 140, and a second electrode 150 over the separator
130. The energy storage device 220 may comprise a second structure
224 comprising a second current collector 120. In some embodiments,
the first electrode 140 can be printed over the first current
collector 110. For example, the first electrode 140 can be printed
on and in direct contact with the first current collector 110. In
some embodiments, the separator 130 can be printed over the first
electrode 140. For example, the separator 130 can be printed on and
in direct contact with the first electrode 140. In some
embodiments, the separator 130 can be printed over the first
electrode 140 such that the separator 130 and the first current
collector 110 encapsulate or substantially encapsulate the first
electrode 140. In some embodiments, the second electrode 150 can be
printed over the separator 130. For example, the second electrode
150 can be printed on and in direct contact with the separator 130.
In some embodiments, assembling the energy storage device 220
includes coupling the first structure 222 and the second structure
224 to form the energy storage device 220. In some embodiments,
coupling the first structure 222 and the second structure 224 can
include bringing the second current collector 120 into contact with
the second electrode 150 such that the second electrode 150 is
between the second current collector 120 and the separator 130.
As described herein, FIGS. 7D and 7E are schematic diagrams of
fully printed energy storage devices. FIG. 7D shows an example of a
vertically stacked energy storage device 230 comprising printed
current collectors 110, 120, electrodes 140, 150 and a separator
130. Referring to FIG. 7D, in some embodiments, a first current
collector 110 of the energy storage device 230 can be printed on a
substrate. In some embodiments, a first electrode 140 can be
printed over the first current collector 110. For example, the
first electrode 140 can be printed on and in direct contact with
the first current collector 110. In some embodiments, a separator
130 can be printed over the first electrode 140. For example, the
separator 130 can be printed on and in direct contact with the
first electrode 140. In some embodiments, a second electrode 150
can be printed over the separator 130. For example, the second
electrode 150 can be printed on and in direct contact with the
separator 130. In some embodiments, a second current collector 120
can be subsequently printed over the second electrode 150. For
example, the second current collector 120 can be printed on and in
direct contact with the second electrode 150. In some embodiments,
the second current collector 120 can be printed over the second
electrode 150 such that the second current collector 120 and the
separator 130 encapsulate or substantially encapsulate the second
electrode 150. In some embodiments, the separator 130 can be
printed over the first electrode 140 such that the separator 130
and the first current collector 110 encapsulate or substantially
encapsulate the first electrode 140.
Referring to FIG. 7E, an energy storage device 240 having laterally
spaced electrodes 140, 150 is shown. The energy storage device 240
can include a first current collector 110 laterally spaced from a
second current collector 120, and a first electrode 140 and a
second electrode 150 over the first current collector 110 and the
second current collector 120, respectively. A separator 130 can be
over the first electrode 140 and the second electrode 150. For
example, the separator 130 can be formed between the first
electrode 140 and the second electrode 150 such that electrodes
140, 150 are electrically insulated from one another. In some
embodiments, the separator 130 facilitates electrical insulation
between the first current collector 110 and the second current
collector 120. In some embodiments, each of the first current
collector 110, the second current collector 120, the first
electrode 140, the second electrode 150, and the separator 130 can
be printed. For example, the first current collector 110 and the
second current collector 120 may be printed on a substrate. In some
embodiments, the first electrode 140 can be printed on and in
direct contact with the first current collector 110. For example,
the first electrode 140 can be printed on and in direct contact
with the first current collector 110. In some embodiments, the
second electrode 150 can be printed over the second current
collector 120. For example, the second electrode 150 can be printed
on and in direct contact with the second current collector 120. In
some embodiments, the separator 130 can be printed over the first
electrode 140 and the second electrode 150, such as on and in
direct contact with both the first electrode 140 and the second
electrode 150. In some embodiments, the separator 130 can be
printed over the first electrode 140 and the second electrode 150
such that the separator 130 and the first current collector 110 and
the second current collector 120 can encapsulate or substantially
encapsulate the first electrode 140 and the second electrode 150,
respectively. In some embodiments, first and second structures each
similar to the first structure 202 and the second structure 204 of
FIG. 7A (e.g., comprising a current collector and an electrode, and
optionally a separator) may be formed with different surface active
materials (e.g., one or more oxides of manganese and ZnO) and then
laterally coupled.
FIG. 8 shows an example embodiment of a separator layer or membrane
300 that may form part of an energy storage device (e.g., the
separator 130 in any of the energy storage devices described with
reference to FIGS. 6 and 7A through 7E). The separator 300 includes
frustules 320. In some embodiments, an energy storage device
includes a separator layer or membrane 300 comprising frustules
320. For example, an energy storage device may include a separator
300 comprising a dispersion including frustules 320. As described
herein, the frustules 320 may be sorted according to a shape,
dimensions, material, porosity, combinations thereof, and/or the
like, such that the separator 300 comprises frustules 320 having a
uniform or substantially uniform shape, dimension (e.g., length,
diameter), porosity, material, combinations thereof, and/or the
like. For example, the separator 300 may include frustules 320
having a cylindrical or substantially cylindrical shape (e.g., as
shown in FIG. 8), a spherical or substantially spherical shape,
another shape, and/or combinations thereof. In some embodiments,
the separator 300 includes frustules 320 having a material and/or
structures applied or formed on a surface of the frustules 320. The
separator 300 may comprise frustules 320 comprising no or
substantially no surface modifying material and/or surface
modifying structures applied or formed on a surface of the
frustules 320 (e.g., as illustrated in FIG. 8). The separator 300
may comprise frustules 320 comprising a material and/or structures
applied or formed on a surface of the frustules 320 to modify a
characteristic or attribute of the frustules 320. The separator 300
may comprise some frustules 320 comprising no or substantially no
surface modifying material and/or surface modifying structures
applied or formed on a surface of the frustules 320 and some
frustules 320 comprising a material and/or structures applied or
formed on a surface of the frustules 320 to modify a characteristic
or attribute of the frustules 320.
The separator 300 may comprise frustules 320 having a mechanical
strength sufficient to enable a stable or substantially stable
separation between a first electrode 140 and a second electrode 150
of an energy storage device (e.g., any of the first electrode 140
and second electrode 150 of FIGS. 6 and 7A through 7E). In some
embodiments, the separator 300 comprises frustules 320 configured
to increase efficiency of an energy storage device, for example by
enabling a reduced separation distance between a first electrode
140 and a second electrode 150 and/or by facilitating flow of ionic
species between a first electrode 140 and a second electrode 150.
For example, frustules 320 may have a uniform or substantially
uniform shape, dimension, porosity, surface modifying material
and/or structures, combinations thereof, and/or the like, for
improved energy storage device efficiency and/or mechanical
strength. The separator 300 of an energy storage device may
comprise cylindrical or substantially cylindrical frustules 320
including walls having a desired porosity, dimensions, and/or
surface modifying material and/or structures.
The separator 300 may comprise one or more layers of frustules 320.
The separator 300 comprising frustules 320 may have a uniform or
substantially uniform thickness. In some embodiments, thickness of
a separator 300 comprising frustules 320 is as thin as possible. In
some embodiments, thickness of a separator 300 comprising frustules
320 is from about 1 .mu.m to about 100 .mu.m, including from about
1 .mu.m to about 80 .mu.m, from about 1 .mu.m to about 60 .mu.m,
from about 1 .mu.m to about 40 .mu.m, from about 1 .mu.m to about
20 .mu.m, from about 1 .mu.m to about 10 .mu.m, from about 5 .mu.m
to about 60 .mu.m, from about 5 .mu.m to about 40 .mu.m, from about
5 .mu.m to about 20 .mu.m, from about 5 .mu.m to about 15 .mu.m,
from about 5 .mu.m to about 10 .mu.m, from about 10 .mu.m to about
60 .mu.m, from about 10 .mu.m to about 40 .mu.m, from about 10
.mu.m to about 20 .mu.m, from about 10 .mu.m to about 15 .mu.m, and
from about 15 .mu.m to about 30 .mu.m. In some embodiments, a
separator comprises a thickness of less than about 100 .mu.m, less
than about 90 .mu.m, less than about 80 .mu.m, less than about 70
.mu.m, less than about 60 .mu.m, less than about 50 .mu.m, less
than about 40 .mu.m, less than about 30 .mu.m, less than about 20
.mu.m, less than about 15 .mu.m, less than about 10 .mu.m, less
than about 5 .mu.m, less than about or 2 .mu.m, less than about or
1 .mu.m, and including ranges bordering and including the foregoing
values. Other thicknesses of the separator 300 are also possible.
For example, the separator 300 may comprise a single layer of
frustules 320 such that the thickness of the separator 300 may
depend at least in part on a dimension of the frustules 320 (e.g.,
a longest axis, a length, or a diameter).
The separator 300 may comprise frustules 320 having a non-uniform
or substantially non-uniform shape, dimension, porosity, surface
modifying material and/or structure, combinations thereof, and/or
the like.
In some embodiments, the separator 300 can include hollow and/or
solid microspheres made from non-electrically conducting materials.
For example, the separator 300 can include hollow and/or solid
microspheres made of glass, alumina, silica, polystyrene, melamine,
combinations thereof, and/or the like. In some embodiments, the
microspheres can have size to facilitate printing of the separator
300. For example, the separator 300 can include microspheres having
a diameter of about 0.1 microns (.mu.m) to about 50 .mu.m. Examples
of separators comprising hollow and/or solid microspheres are
provided in U.S. patent application Ser. No. 13/223,279, entitled,
"PRINTABLE IONIC GEL SEPARATION LAYER FOR ENERGY STORAGE DEVICES,"
filed Aug. 9, 2012, which is incorporated herein by reference in
its entirety.
In some embodiments, the separator 300 comprises a material
configured to reduce electrical resistance between a first
electrode 140 and a second electrode 150 of an energy storage
device. For example, referring again to FIG. 8, in some
embodiments, the separator 300 comprises an electrolyte 340. The
electrolyte 340 may include any material that facilitates the
conductivity of ionic species, including, for example, a material
comprising mobile ionic species that can travel between a first
electrode 140 and a second electrode 150 of an energy storage
device. The electrolyte 340 may comprise any compound that may form
ionic species, including but not limited to sodium sulfate
(Na.sub.2SO.sub.4), lithium chloride (LiCl), and/or potassium
sulfate (K.sub.2SO.sub.4). In some embodiments, the electrolyte 340
comprises an acid, a base, or a salt. In some embodiments, the
electrolyte 340 comprises a strong acid, including but not limited
to sulfuric acid (H.sub.2SO.sub.4) and/or phosphoric acid
(H.sub.3PO.sub.4), or a strong base, including but not limited to
sodium hydroxide (NaOH) and/or potassium hydroxide (KOH). In some
embodiments, the electrolyte 340 comprises a solvent having one or
more dissolved ionic species. For example, the electrolyte 340 may
comprise an organic solvent. In some embodiments, the electrolyte
340 includes an ionic liquid or an organic liquid salt. The
electrolyte 340 may comprise an aqueous solution having an ionic
liquid. The electrolyte 340 may comprise a salt solution having an
ionic liquid. In some embodiments, the electrolyte 340 comprising
an ionic liquid includes propylene glycol and/or acetonitrile. In
some embodiments, the electrolyte 340 comprising an ionic liquid
includes an acid or base. For example, the electrolyte 340 may
comprise an ionic liquid combined with potassium hydroxide (e.g.,
addition of a 0.1 M solution of KOH).
In some embodiments, the electrolyte 340 can include one or more
ionic liquids and/or one or more salts described in U.S. patent
application Ser. No. 14/249,316, entitled "PRINTED ENERGY STORAGE
DEVICE," filed Apr. 9, 2014, which is incorporated herein by
reference in its entirety.
In some embodiments, the separator 300 comprises a polymer 360,
such as a polymeric gel. The polymer 360 may be combined with an
electrolyte 340. A suitable polymer 360 may exhibit electrical and
electrochemical stability, for example maintaining integrity and/or
functionality when combined with an electrolyte 340, during
electrochemical reactions, and/or subjected to an electric
potential (e.g., an electric potential existing between the
electrodes 140, 150 of the energy storage device). In some
embodiments, the polymer 360 can be an inorganic polymer. In some
embodiments, the polymer 360 can be a synthetic polymer. The
separator 300 may include a polymer 360 comprising, for example,
cellulose (e.g., cellophane), polyamide (e.g., nylon),
polypropylene, polyolefin, polyethylene (e.g., radiation-grafted
polyethylene), poly(vinylidene fluoride), poly(ethylene oxide),
poly(acrylonitrile), poly(vinyl alcohol), poly(methyl
methacrylate), poly(vinyl chloride), poly[bis(methoxy ethoxy
ethoxyphosphazene)], poly(vinyl sulfone), poly(vinyl pyrrolidone),
poly(propylene oxide), copolymers thereof, combinations thereof,
and/or the like. In some embodiments, the polymer 360 comprises
polytetrafluoroethylene (PTFE), including for example an aqueous
solution comprising a dispersion of PTFE in water (e.g., a
Teflon.RTM. aqueous suspension). In some embodiments, the separator
300 can comprise asbestos, potassium titanate fibers, fibrous
sausage casing, borosilicate glass, zirconium oxide, combinations
thereof, and/or the like. In some embodiments, the electrolyte 340
is immobilized within or on the polymer 360 to form a solid or
semi-solid substance. In some such embodiments, the electrolyte 340
is immobilized on or within a polymeric gel, for example to form an
electrolytic gel.
In some embodiments, the separator 300 optionally comprises an
adhesive material to enable improved adherence of frustules 320
within the separator 300 and/or between the separator 300 and a
first electrode 140 and/or a second electrode 150 of an energy
storage device. In some embodiments, the adhesive material
comprises a polymer 360. For example, the adhesive material may
comprise a polymer 360 that exhibits electrical and electrochemical
stability, and provides sufficient adhesion within the separator
300 and/or between the separator 300 and a first electrode 140
and/or a second electrode 150 of an energy storage device.
In some embodiments, an ink for printing a separator of an energy
storage device comprises a plurality of frustules having no or
substantially no surface modifications, polymer, ionic liquid,
electrolyte salt, and/or a solvent. Examples of suitable solvents
are provided in U.S. patent application Ser. No. 14/249,316,
entitled "PRINTED ENERGY STORAGE DEVICE," filed Apr. 9, 2014, which
is incorporated herein by reference in its entirety. In some
embodiments, a solvent for an ink used to print a separator can
comprise dimethyl formamide (DMF), dimethyl acetamide (DMAC),
tetramethyl urea, dimethyl sulfoxide (DMSO), triethyl phosphate,
n-methyl-2-pyrrolidone (NMP), combinations thereof, and/or the
like. In some embodiments, the ink for printing the separator
comprises the following composition: about 5 weight % to about 20
weight % frustules having no surface modifications (e.g., purified
frustules), about 3 weight % to about 10 weight % of the polymer
component (e.g., polyvinylidene fluoride, for example Kynar.RTM.
ADX commercially available from Arkema Inc. of King of Prussia,
Pa.), about 15 weight % to about 40% ionic liquid (e.g.,
1-ethyl-3-ethylimidazolium tetrafluoroborate), about 1 weight % to
about 5% salt (e.g., zinc tetrafluoroborate), about 25 weight % to
about 76 weight % solvent (e.g., N-Methyl-2-pyrrolidone). In some
embodiments, other polymers, ionic liquids, salts (e.g., other zinc
salt) and/or solvents may also be suitable.
In some embodiments, a process for preparing the ink for a
separator can include dissolving the binder in the solvent. For
example, dissolving the binder in the solvent may include heating
the mixture comprising the binder and the solvent for about 5 min
to about 30 min at a temperature of about 80.degree. C. to about
180.degree. C. In some embodiments, the heating can be performed
using a hot plate. In some embodiments, the ionic liquid and
electrolyte salt can be added to the mixture, such as while the
mixture is warm after being heated. The binder, solvent ionic
liquid and electrolyte salt may be stirred to facilitate desired
mixing, such as for about 5 min to about 10 min. In some
embodiments, the frustules can be subsequently added. Addition of
the frustules may be facilitated by mixing, such as by using a
planetary centrifugal mixer. Mixing may be performed using the
planetary centrifugal mixer for about 1 min to about 15 min.
FIG. 9 shows an example electrode layer or membrane 400 that may
form part of an energy storage device (e.g., any of the energy
storage devices as described with reference to FIGS. 6 and 7A
through 7E). The electrode 400 includes frustules 420. In some
embodiments, an energy storage device includes one or more
electrode layers or membranes 400 comprising frustules 420 (e.g.,
the first electrode 140 and/or the second electrode 150 of any of
the energy storage devices as described with reference to FIGS. 6
and 7A through 7E). For example, an energy storage device may
include an electrode layer or membrane 400 comprising a dispersion
including frustules 420. As described herein, the frustules 420 may
be sorted according to a shape, dimensions, material, porosity,
combinations thereof, and/or the like, such that the electrode 400
comprises frustules 420 having a uniform or substantially uniform
shape, dimension (e.g., length, diameter), porosity, material,
combinations thereof, and/or the like. For example, the electrode
400 may include frustules 420 having a cylindrical or substantially
cylindrical shape (e.g., as shown in FIG. 9), a spherical or
substantially spherical shape, another shape, and/or combinations
thereof. In some embodiments, the electrode 400 includes frustules
420 having a material and/or structures applied or formed on a
surface of the frustules 420. The electrode 400 may comprise
frustules 420 comprising no or substantially no surface modifying
material, and may be insulating, and/or may have surface modifying
structures applied or formed on a surface of the frustules 420. The
electrode 400 may comprise frustules 420 comprising a material
and/or structures applied or formed on a surface of the frustules
420 to modify a characteristic or attribute of the frustules 420
(e.g., as schematically illustrated in FIG. 9 by the chicken
foot-shaped features on the surfaces of the frustules 420). The
electrode 400 may comprise some frustules 420 comprising no or
substantially no surface modifying material and/or surface
modifying structures applied or formed on a surface of the
frustules 420 and some frustules 420 comprising a material and/or
structures applied or formed on a surface of the frustules 420 to
modify a characteristic or attribute of the frustules 420.
The electrode 400 may comprise frustules 420 selected for
mechanical strength such that an energy storage device including
the electrode 400 may withstand compressive force and/or shape
modifying deformation. In some embodiments, the electrode 400
comprises frustules 420 configured to increase efficiency of an
energy storage device, for example by facilitating flow of ionic
species within the electrode 400 and/or between the electrode 400
and other parts of the energy storage device. For example,
frustules 420 may have a uniform or substantially uniform shape,
dimension, porosity, surface modifying material and/or structures,
combinations thereof, and/or the like, for improved energy storage
device efficiency and/or mechanical strength. The electrode 400 of
an energy storage device may comprise cylindrical or substantially
cylindrical frustules 420 including walls having a desired
porosity, dimensions, and/or surface modifying material and/or
structures.
The electrode 400 may comprise one or more layers of frustules 420.
The electrode 400 comprising frustules 420 may have a uniform or
substantially uniform thickness. In some embodiments, thickness of
an electrode 400 comprising frustules 420 depends at least in part
on resistance, amount of available material, desired energy device
thickness, or the like. In some embodiments, thickness of an
electrode 400 comprising frustules 420 is from about 1 .mu.m to
about 100 .mu.m, including from about 1 .mu.m to about 80 .mu.m,
from about 1 .mu.m to about 60 .mu.m, from about 1 .mu.m to about
40 .mu.m, from about 1 .mu.m to about 20 .mu.m, from about 1 .mu.m
to about 10 .mu.m, from about 5 .mu.m to about 100 .mu.m, including
from about 5 .mu.m to about 80 .mu.m, from about 5 .mu.m to about
60 .mu.m, from about 5 .mu.m to about 40 .mu.m, from about 5 .mu.m
to about 20 .mu.m, from about 5 .mu.m to about 10 .mu.m, from about
10 .mu.m to about 60 .mu.m, from about 10 .mu.m to about 40 .mu.m,
from about 10 .mu.m to about 20 .mu.m, from about 10 .mu.m to about
15 .mu.m, and from about 15 .mu.m to about 30 .mu.m. In some
embodiments, thickness of an electrode 400 comprising frustules 420
is less than about 100 .mu.m, less than about 90 .mu.m, less than
about 80 .mu.m, less than about 70 .mu.m, less than about 60 .mu.m,
less than about 50 .mu.m, less than about 40 .mu.m, less than about
30 .mu.m, less than about 20 .mu.m, less than about 10 .mu.m, less
than about 5 .mu.m, less than about 2 .mu.m, or less than about 1
.mu.m, and including ranges bordering and including the foregoing
values. Other thicknesses of the separator 300 are also
possible.
The electrode 400 may comprise frustules 420 having a non-uniform
or substantially non-uniform shape, dimension, porosity, surface
modifying material and/or structure, combinations thereof, and/or
the like.
In some embodiments, the electrode 400 optionally comprises a
material to enhance the conductivity of electrons within the
electrode 400. For example, referring again to FIG. 9, in some
embodiments, the electrode 400 comprises electrically conductive
filler 460 to improve electrical conductivity within the electrode
400. Electrically conductive filler 460 may comprise a conductive
carbon material. For example, electrically conductive filler 460
may comprise graphitic carbon, graphene, carbon nanotubes (e.g.,
single-wall and/or multi-wall), combinations thereof, and/or the
like. In some embodiments, electrically conductive filler 460 can
include a metallic material (e.g., silver (Ag), gold (Au), copper
(Cu), nickel (Ni), and/or platinum (Pt)). In some embodiments,
electrically conductive filler 460 can include a semiconductor
material (e.g., silicon (Si), germanium (Ge)), and/or a
semiconductor-containing alloy (e.g., an aluminum-silicon (AlSi)
alloy). In energy storage devices 100 comprising a plurality of
electrodes 400, the electrodes 400 may include different frustules
and/or different additives, for example including different ions
and/or ion-producing species. In some embodiments, the electrode
400 may comprise an electrolyte, for example the electrolyte 340
described herein with respect to the separator 300 of FIG. 8. In
some embodiments, the electrode 400 may comprise a polymer, for
example the polymer 360 described herein with respect to the
separator 300 of FIG. 8. In some embodiments, the electrode 400 can
include one or more active materials (e.g., free active materials,
such as active materials in addition to nanostructured active
materials on one or more surfaces of diatom frustules).
In some embodiments, the electrode 400 can include a binder. The
binder may comprise a polymer. Suitable polymers, polymeric
precursors and/or polymerizable precursors, for an electrode
binder, can include for example, polyvinyl pyrrolidone (PVP),
polyvinyl alcohol (PVA), polyvinylidene fluoride, polyvinylidene
fluoride-trifluoroethylene, polytetrafluoroethylene,
polydimethylsiloxane, polyethylene, polypropylene, polyethylene
oxide, polypropylene oxide, polyethylene glycolhexafluoropropylene,
polyethylene terephthalatpolyacrylonitrile, polyvinyl butyral,
polyvinylcaprolactam, polyvinyl chloride; polyimide polymers and
copolymers (e.g., aliphatic, aromatic and/or semi-aromatic
polyimides), polyamides, polyacrylamide, acrylate and
(meth)acrylate polymers and copolymers such as
polymethylmethacrylate, polyacrylonitrile, acrylonitrile butadiene
styrene, allylmethacrylate, polystyrene, polybutadiene,
polybutylene terephthalate, polycarbonate, polychloroprene,
polyethersulfone, nylon, styrene-acrylonitrile resin; polyethylene
glycols, clays such as hectorite clays, garamite clays,
organomodified clays; saccharides and polysaccharides such as guar
gum, xanthan gum, starch, butyl rubber, agarose, pectin; celluloses
and modified celluloses such as hydroxyl methylcellulose,
methylcellulose, ethyl cellulose, propyl methylcellulose, methoxy
cellulose, methoxy methylcellulose, methoxy propyl methylcellulose,
hydroxy propyl methylcellulose, carboxy methylcellulose, hydroxy
ethylcellulose, ethyl hydroxyl ethylcellulose, cellulose ether,
cellulose ethyl ether, chitosan, their copolymers, combinations
thereof, and/or the like.
In some embodiments, the electrode 400 can include a corrosion
inhibitor and/or one or more other functional additives. In some
embodiments, a corrosion inhibitor can include one or more surface
active organic compounds. In some embodiments, a corrosion
inhibitor can comprise glycols, silicates, mercury (Hg), cadmium
(Cd), lead (Pb), gallium (Ga), indium (In), antimony (Sn), bismuth
(Bi), combinations thereof, and/or the like.
In some embodiments, the electrode 400 optionally comprises an
adhesive material to enable improved adhesion of frustules 420
within the electrode 400 and/or between the electrode 400 and
another component of the energy storage device such as a separator
130 and/or a current collector 110, 120. In some embodiments, the
adhesive material in the electrode 400 comprises a polymer, for
example the polymer 360 described herein.
In some embodiments, an ink for printing an electrode of an energy
storage device can comprise a plurality of frustules comprising
nanostructures formed on one or more surfaces, a conductive filler
(e.g., carbon nanotubes, graphite), a binder component, electrolyte
(e.g., ionic liquid, electrolyte salt), and/or a solvent. For
example, the electrolyte may have a composition as described
herein. In some embodiments, one or more solvents described with
reference to a separator ink may also be suitable for the ink for
printing the electrode. In some embodiments, a solvent for an ink
used to print an electrode can comprise dimethyl formamide (DMF),
dimethyl acetamide (DMAC), tetramethyl urea, dimethyl sulfoxide
(DMSO), triethyl phosphate, n-methyl-2-pyrrolidone (NMP),
combinations thereof, and/or the like. In some embodiments, the ink
for printing the electrode can comprise frustules having an oxide
of manganese nanostructures formed on one or more surfaces. In some
embodiments, the ink for printing the electrode comprises frustules
having ZnO nanostructures formed on one or more surfaces.
In some embodiments, ink for printing an electrode of an energy
storage comprising an oxide of manganese can have the following
composition: about 10 weight % to about 20 weight % frustules
having one or more surfaces covered by the oxide of manganese,
about 0.2 weight % to about 2 weight % carbon nanotubes (e.g.,
multi-wall carbon nanotubes, for example commercially available
from SouthWest NanoTechnologies of Norman, Okla.), up to about 10
weight % graphite (e.g., C65 commercially available from Timcal
Graphite and Carbon, of Switzerland), about 1 weight % to about 5
weight % binder (e.g., polyvinylidene fluoride, such as HSV 900
Kynar.RTM. commercially available from Arkema Inc. of King of
Prussia, Pa.), about 2 weight % to about 15 weight % ionic liquid
(e.g., 1-ethyl-3-ethylimidazolium tetrafluoroborate), and about 48
weight % to about 86.8 weight % solvent (e.g.,
N-Methyl-2-pyrrolidone). In some embodiments, the oxide of
manganese has the formula Mn.sub.xO.sub.y where x is about 1 to
about 3 and y is about 1 to about 4. For example, the ink may be
printed to form a cathode of a battery.
In some embodiments, ink for printing an electrode of an energy
storage comprising ZnO can have the following composition: about 10
weight % to about 20 weight % frustules comprising ZnO
nanostructures formed thereon, about 0.2 weight % to about 2 weight
% carbon nanotubes (e.g., multi-wall carbon nanotubes, for example
commercially available from SouthWest NanoTechnologies of Norman,
Okla.), up to about 10 weight % graphite (e.g., C65 commercially
available from Timcal Graphite and Carbon of Switzerland), about 1
weight % to about 5 weight % binder (e.g., polyvinylidene fluoride,
such as HSV 900 Kynar.RTM. commercially available from Arkema Inc.
of King of Prussia, Pa.), about 2 weight % to about 15 weight %
ionic liquid (e.g., 1-ethyl-3-ethylimidazolium tetrafluoroborate),
about 0.3 weight % to about 1% weight % electrolyte salt (e.g.,
zinc tetrafluoroborate), and about 47 weight % to about 86.5 weight
% solvent (e.g., N-Methyl-2-pyrrolidone). For example, the ink may
be printed to form an anode of a battery.
In some embodiments, the carbon nanotubes can comprise multi-wall
and/or single wall carbon nanotubes. In some embodiments, other
types of graphite, polymer binder, ionic liquid and/or solvent can
also be suitable.
In some embodiments, a process for preparing the ink for printing
the electrode can be configured to provide desired dispersion of
carbon nanotubes in the ink, saturate the frustules with the ionic
liquid (e.g., providing ionic liquid within, on interior surfaces,
exterior surfaces, and/or within pores, of frustules) and/or
thoroughly mix components of the ink. In some embodiments, a
process of preparing the ink comprises dispersing the carbon
nanotubes in the ionic liquid. In some embodiments, the carbon
nanotubes can be dispersed in the ionic liquid using an automated
mortar and pestle. In some embodiments, the carbon nanotubes and
the ionic liquid may then be dispersed in the solvent. The carbon
nanotubes and ionic liquid may be dispersed in the solvent using an
ultrasonic tip. In some embodiments, the frustules comprising
nanostructures formed thereon (e.g., oxide of manganese or ZnO
nanostructures) and graphite may be added to the carbon nanotubes,
ionic liquid, and solvent, and stirred using a centrifugal mixer.
In some embodiments, the electrolyte salt can also be added to the
carbon nanotubes, ionic liquid, and solvent, along with the
frustules and graphite, and stirred using a centrifugal mixer. For
example, the frustules, graphite, carbon nanotubes, ionic liquid,
solvent, and/or electrolyte salt, may be mixed using a planetary
centrifugal mixer for about 1 minutes (min) to about 10 min. In
some embodiments, a solution comprising the polymer binder in the
solvent can be added to the mixture comprising the frustules,
graphite, carbon nanotubes, ionic liquid, solvent, and/or
electrolyte salt, and heated. The solution comprising the polymer
binder and the solvent can have about 10 weight % to about 20
weight % of the polymer binder. The mixture comprising the polymer
binder, frustules, graphite, carbon nanotubes, ionic liquid,
solvent, and/or electrolyte salt, can be heated to a temperature of
about 80.degree. C. to about 180.degree. C. In some embodiments,
the heating can be performed for about 10 min to about 30 min. In
some embodiments, a hot plate can be used for heating. In some
embodiments, stirring can be performed while heating (e.g., with a
mixing rod).
FIGS. 10 through 13 show electrical performances of examples of
printed batteries comprising oxides of manganese (e.g., oxides
having the formula Mn.sub.xO.sub.y where x is about 1 to about 3
and y is about 1 to about 4) cathode and a ZnO anode fabricated
using processes described herein. FIG. 10 is a discharge curve
graph for a printed Mn.sub.xO.sub.y and ZnO battery, where the
cathode included a plurality of frustules comprising oxides of
manganese nanostructures formed thereon and the anode included a
plurality of frustules comprising ZnO nanostructures formed
thereon. The battery potential expressed in Volts (V) on the y-axis
and the duration of discharge expressed in hours (hrs) on the
x-axis. The battery was a screen printed 1.27 centimeter (cm) by
1.27 cm square (i.e. 0.5 inch (in) by 0.5 inch square). The battery
included printed current collectors, anode, cathode, and separator.
The anode and cathode each had an average thickness of about 40
microns (.mu.m). The cathode had a total weight of about 0.023
grams (g), and a weight of the oxides of manganese was about 0.01
g. The weight of active material, ZnO, in the anode was in
excess.
In FIG. 10, the battery was discharged from a fully or
substantially fully charged state to the cut-off voltage of about
0.8 V. The battery was discharged at about 0.01 amperes/gram (A/g).
The battery demonstrated a capacity of about 1.28 milli-ampere hour
(mAh), and a capacity of about 128 milli-ampere hour/gram (mAh/g),
based on the weight of the cathode active material. FIG. 11 shows
the capacitance performance of the printed battery of FIG. 10 after
a number charge-discharge cycles. The battery was cycled 40 times
and the capacitance performance of each cycle is shown on the
y-axis as a % of the initial capacitance. As shown in FIG. 11, the
capacitance performance can be improved after a number of
charge-discharge cycles.
FIG. 12 is a charge-discharge curve of another example of a printed
Mn.sub.xO.sub.y and ZnO battery, showing the potential performance
of each charge-discharge cycle as a function of time during three
charge-discharge cycles. The potential is shown on the y-axis in
Volts (V), and time is expressed on the x-axis in hours (hrs). The
printed battery was a screen printed 1.27 centimeter (cm) by 1.27
cm square (i.e. 0.5 inch (in) by 0.5 inch square). The cathode of
the battery included a plurality of frustules comprising oxides of
manganese nanostructures formed thereon and the anode included a
plurality of frustules comprising ZnO nanostructures formed
thereon. The battery included printed current collectors, anode,
cathode, and separator. The anode and cathode each had an average
thickness of about 40 microns (.mu.m). The cathode had a total
weight of about 0.021 grams (g), and the weight of the oxides of
manganese was about 0.01 g. The weight of active material (e.g.,
ZnO) in the anode was in excess. The printed battery of FIG. 12 was
charged and discharged at about 0.01 amperes/gram (A/g), based on
the weight of active material in the cathode. FIG. 13 is a
charge-discharge curve of the printed Mn.sub.xO.sub.y and ZnO
battery of FIG. 12, where the charge and discharge was performed at
about 0.04 A/g. Both sets of curves show good repeatability for
both charge and discharge, indicative that the printed
Mn.sub.xO.sub.y/ZnO battery can be an effective rechargeable
battery.
Supercapacitors Comprising Surface-Modified Diatoms
In the above, energy storage devices that derive various advantages
arising from diatomaceous frustules have been described. In the
following, one particular type of such energy storage devices,
referred to herein and in the relevant industry as supercapacitors,
are described in detail. Supercapacitors, sometimes also referred
to as ultracapacitors, electric double layer capacitors (EDLC) or
electrochemical capacitors, are relatively new energy storage
devices whose characteristics are advantageously similar to
traditional electrostatic capacitors in some aspects while being
similar to traditional batteries, e.g., secondary batteries, in
some other aspects.
Similar to certain batteries, supercapacitors have a cathode or a
positive electrode and an anode or a negative electrode that are
separated by a porous separator and an electrolyte. For example,
the separator may comprise a dielectric material permeable to ions
and soaked in the electrolyte. Ion transport which occurs from one
electrode to the other as part of an electrochemical reaction
during charge or discharge of a battery does not occur in
supercapacitors.
While supercapacitors are similar to traditional electrostatic
capacitors in some aspects, e.g., relatively fast charging
capability, they have much higher capacitance compared to
traditional electrostatic capacitors. Unlike traditional
electrostatic capacitors that store energy in electrodes separated
by a dielectric, supercapacitors store energy at one or both of
interfaces between a cathode and an electrolyte and an anode and
the electrolyte.
Capacitance values of supercapacitors may be much higher than
traditional electrostatic capacitors. Some supercapacitors have
lower voltage limits compared to traditional electrostatic
capacitors. For example, some supercapacitors are operationally
limited to about 2.5-2.8 V. Some supercapacitors may operate at
voltages of 2.8 V and higher. Certain such supercapacitors may
exhibit a reduced service life.
Supercapacitors generally have much higher power density than
batteries because they can transport charge much faster than
batteries. Supercapacitors generally have much lower internal
resistance compared to batteries and, as a result, they do not
generate as much heat during quick charge/discharge. Some
supercapacitors can be charged and discharged millions of times,
while many secondary batteries can have significantly shorter
typical life cycle of 500-10000 times. Some supercapacitors have
significantly lower energy density compared to batteries. Some
commercial supercapacitors are more expensive (higher cost per
Watt) than commercial batteries.
Because of these and other characteristics, supercapacitors are
used in applications in which many rapid charge/discharge cycles
may be needed rather than long term energy storage. For example,
applications of larger units of supercapacitors include cars,
buses, trains, cranes and elevators, to name a few, where they are
used for regenerative braking, short-term energy storage or
burst-mode power delivery. Applications of smaller units of
supercapacitors include memory backup for static random-access
memory (SRAM). Other current or future applications of
supercapacitors include various consumer electronics, including
mobile phones, laptops, electric cars and various other devices in
which batteries are used. Because they can be recharged much faster
compared to batteries, they are especially attractive for devices
that can benefit from faster charge rates, e.g., minutes instead of
hours that current electric vehicles or mobile phones may spend
charging.
In some devices, supercapacitors are used in conjunction with
batteries to take advantage of advantageous characteristics of
both. In these applications, supercapacitors are used when a quick
charge is needed to fill a short-term power need, whereas batteries
are used to provide long-term energy. Combining the two into a
hybrid energy storage device can satisfy both needs while reducing
battery stress, which may in turn enable a longer service life of
the battery and the supercapacitor.
Because the capacitance of supercapacitors is directly proportional
to the effective surface area of the electrodes, it is desirable
for the electrodes of supercapacitors to have relatively large
effective surface areas. The relatively large effective surface
area can be realized by utilizing electrode materials having high
surface to volume ratios. As described above, because of their
nanoporous structure, frustules can advantageously provide a very
large effective surface area to serve as a substrate on which a
surface active material of supercapacitors are formed. As described
herein in the context of supercapacitors, a surface active material
refers to a portion of the electrode that forms an interface with
an electrolyte to substantially give rise to capacitance caused by
at least one of supercapacitance mechanisms, e.g., electric double
layer capacitance and/or pseudo capacitance, as described below in
more detail. Nanostructures, e.g., nanoparticles or nanotubes, can
additionally or alternatively provide very large surface areas for
a given volume of the surface active material compared to, e.g., a
thin film formed of the same material. As described herein in the
context of supercapacitors, a nanostructure refers to a solid
material having at least one axial dimension that is submicron,
e.g., about smaller than about 1000 nm, 500 nm, 200 nm, 100 nm or a
dimension that is within a range defined by any of these
values.
A nanostructure can have any shape described above, e.g., a
nanowire, a nanosheet, a nanotube, a nanoplate, a nanoparticle, a
nanobelt, a nanodisk and a rosette shaped nanostructure. The
nanostructure can also have any three dimensional geometrical
shapes, e.g., a sphere, a cylinder, a cone, a spheroid, an
ellipsoid, a tetrahedron, a pyramid, a prism, a cube, a cuboid, a
plate, a disc and a rod to name a few. In some implementations, the
nanostructure can be selected to have a particular shape based on
the crystal structure of the nanostructure. As described above, the
inventors have discovered inventive methods of modifying the
surfaces of frustules with various surface active materials. The
inventors have recognized that, by synergizing the very high
effective surface area of the frustules and the very high
surface-to-volume ratio of nanostructured surface active materials,
supercapacitors having higher power and energy densities than
existing supercapacitors can be realized. For example, by modifying
surfaces of frustules with nanostructured surface active material
having a large surface to volume ratio, the inventors have realized
supercapacitors that benefit from the synergistic effect of the
frustules and the nanostructured surface active material.
According to various embodiments, a supercapacitor comprises a pair
of electrodes contacting an electrolyte. In some embodiments, the
electrodes may be interposed by the electrolyte and may further
comprise a separator, e.g., immersed in the electrolyte. In various
embodiments, one or both of the electrodes comprise a plurality of
frustules and surface active materials. The surface active
materials contact the electrolyte to give rise to one or more
supercapacitance mechanisms described below. In some embodiments,
each of the frustules has formed thereon the surface active
materials. The surface active materials may be nanostructured to
take advantage of the high surface area of the frustules and/or to
take advantage of the high surface to volume ratio of the surface
active material, thereby giving rise to improved supercapacitance
performance, including higher power and/or energy density. For
example, the surface active materials may be in the form of a
plurality of nanostructures covering surfaces of the frustules. The
nanostructures can include one or more of zinc oxide
nanostructures, manganese oxide nanostructures or carbon
nanostructures. The performance of the disclosed supercapacitors
benefits from the synergistic effect of the high surface area
provided by the nanoporosity of the structure of diatom frustules
and the high surface to volume ratio of the surface active
materials. Because the surface active materials, e.g.,
nanostructures, are grown on diatom frustules, they are not
agglomerated, and relatively larger portions of their surface area
are accessible to electrolyte. Because the diatoms frustules are
nanoporous, the electrolyte has direct access to the nanostructures
and can easily move throughout the device. The disclosed
supercapacitors can advantageously be manufactured using scalable
techniques such as printing. Manufactured supercapacitors can be
used as small scale devices, for example in printed electronics,
and/or can be produced in large volume and folded in a shape for
more powerful applications.
Without being bound to any theory, supercapacitors can store energy
by different mechanisms, which include electric double-layer
capacitance and/or pseudocapacitance. Double layer capacitance has
electrostatic characteristics, while pseudocapacitance has
electrochemical characteristics. The different mechanisms are
described in more detail below. Depending on whether the storage
mechanism has double-layer capacitance characteristics and/or
pseudocapacitance characteristics, and depending on whether the
supercapacitor has two same or symmetric electrodes or two
different or asymmetric electrodes, the supercapacitor comprising
one or both of the electrodes having a plurality of frustules
coated with nanostructured surface active material can be
configured as one of three distinct groups of supercapacitors.
A first group of supercapacitors has both electrodes configured as
pseudo capacitors, where each of the electrodes comprises frustules
and a transition metal oxide (e.g., manganese oxide or zinc oxide)
and is configured to give rise to pseudo capacitance. For example,
the frustules may have a transition metal oxide formed thereon in
the form of nanostructures. A second group of supercapacitors has
both electrodes configured as EDLCs, where each of the electrodes
comprises frustules and carbon (e.g., carbon nanotubes) and is
configured to give rise to double layer capacitance. For example,
the frustules may have carbon formed thereon in the form of
nanostructures. A third group of supercapacitors, which may be
referred to as hybrid supercapacitors, has one of the electrodes
that is configured as a EDLC and the other of the electrodes that
is configured a pseudo capacitor. When included as part of a hybrid
capacitor, the electrode configured as the pseudo capacitor may
serve as a cathode or a positively charged electrode, and the
electrode configured as the EDLC may serve as an anode or a
negatively charged electrode. Without being bound to any theory,
operational principles of the three groups of supercapacitors are
described herein.
FIG. 14A illustrates a cross-sectional view of a supercapacitor
1400 having both electrodes configured as a double-layer capacitor.
FIG. 14B illustrates a cross-sectional view of the supercapacitor
of FIG. 14A in operation, where a voltage is applied across the
electrodes. FIGS. 14A and 14B illustrate the supercapacitor 1400 in
a discharged state and a charged state, respectively. The
supercapacitor 1400 includes a first electrode 1440, which may be
positively charged in operation, and a second electrode 1450, which
may be negatively charged in operation. The supercapacitor 1400
optionally includes first and second current collectors 1410, 1420
electrically coupled to the electrodes 1440, 1450, respectively.
The first and second electrodes 1440, 1450 are interposed by a
separator 1430 and are ionically connected to each other via an
electrolyte 1460 filling the gap between the first and second
electrodes 1440, 1450. The electrolyte 1460 comprises a mixture of
positive and negative ions 1470, 1480 dissolved in a solvent. The
surface of each of the two electrodes 1440, 1450 contacts the
electrolyte 1460 to form active interfaces. At the active
interfaces between the electrodes 1440, 1450, and the electrolyte
1460, the double layer capacitance effect arises.
Referring to FIG. 14A, in the discharged state, the positive ions
1470 and negative ions 1480 may be dispersed randomly. In
operation, referring to FIG. 14B, applying a voltage across the
first and second electrodes 1440, 1450, e.g., by negatively
charging the second current collector 1420 relative to the first
current collector 1410 and/or positively charging the first current
collector 1410 relative to the second current collector 1420,
causes both electrodes 1440, 1450 to generate electrical double
layers. Each of the electrical double layers includes two layers of
charge, as illustrated in FIG. 14B. Without being bound to any
theory, for example, a layer of electrostatic charge, e.g., a sheet
of negative electronic charge, may form at the surface of the
second electrode 1450, e.g., at the surface of the surface active
material, and an opposite layer of electrostatic charge, e.g., a
sheet of positive ionic charge, may form adjacent to the surface of
the electrode 1450 in the electrolyte 1460. The two sheets of
charge are separated by a layer 1490, e.g., a monolayer, of
molecules of the solvent of the electrolyte 1460, sometimes
referred to as inner Helmholtz plane (IHP). This layer 1490 of
solvent molecules serves as a layer of dielectric giving rise to a
first capacitance (C.sub.d1) at the second electrode 1450 side. In
an analogous manner, a layer 1500 of solvent molecules forms
between a layer of electrostatic charge, e.g., a positive
electronic charge layer at the surface of the first electrode 1440,
e.g., at the surface of the surface active material, and an
opposite layer of electrostatic charge, e.g., a negative ionic
charge, may form adjacent to the surface of the first electrode
1440 in the electrolyte 1460. The layer 1500 of solvent molecules
serves as another layer of dielectric giving rise to a second
capacitance (C.sub.d2) at the side of the first electrode 1440.
As described herein, each of the layers 1490, 1500 of solvent
molecules formed adjacent to the first and second electrodes 1450,
1440, respectively, serves as a dielectric layer giving rise to the
capacitances C.sub.d1 and C.sub.d2. The capacitors formed at the
second electrode 1450 and the first electrode 1440 are electrically
connected in series by the electrolyte 1460 to provide a series
supercapacitance Cs that can be expressed as:
.times..times..times..times..times. ##EQU00001##
For a given solvent of the electrolyte 1460, the amount of charge
stored per unit voltage in an EDLC is a function of the electrode
size. Similar to classical electrostatic capacitance, the
capacitance of Cal arising from the first double layer capacitor on
the side of the second electrode 1450 may be approximated by
C.sub.d1=.epsilon..sub.1dd.sub.1, Eq. 2 where .epsilon..sub.1 is
the permittivity of the solvent of the electrolyte 1460, and
d.sub.1 is the effective thickness of the layer 1490 of solvent
molecules formed adjacent to the second electrode 1450. Similarly,
the capacitance C.sub.d2 arising from the second double layer on
the side of the first electrode 1440 may be approximated by
C.sub.d2=.epsilon..sub.2d.sub.2, Eq. 3 where .epsilon..sub.2 is the
permittivity and d.sub.2 is the effective thickness of the layer
1500 of solvent molecules of the electrolyte 1460 formed adjacent
to the second electrode 1440. The stored energy in each of the
double-layers is approximately linear with respect to the
capacitance, and corresponds to the concentration of the adsorbed
ions. The energy E stored in the supercapacitor can be expressed
as:
.times..times. ##EQU00002## where C.sub.s is the supercapacitor
capacitance described above, A is the effective surface area of the
electrodes, and V is the voltage. The power of the supercapacitor
can be expressed as:
.times..times. ##EQU00003## where R is the equivalent series
resistance of the supercapacitor. According to the above
expressions of the capacitance, energy and power, the higher power
and energy of the supercapacitors are achieved by, for a given
electrolyte, increasing the surface area (A) of electrodes 1450,
1440, increasing the voltage (V) the supercapacitor and by
decreasing the equivalent resistance (R) attributable to the
electrodes, electrolytes and interfaces between the electrode
materials and supercapacitor layers. The electric double-layer
capacitance values are extremely high relative to traditional
electrostatic capacitors with similar macroscopic electrode sizes,
arising in part from the extremely thin layers 1490, 1500 of
solvent molecules, which can be as thin as a monolayer thickness,
e.g., on the order of a few angstroms (0.3-0.8 nm), which can of
the order of the Debye length. The active area of the electrodes
are also extremely high as described above, arising from the large
surface area of the frustules, whose effective surface area is
further enhanced by the nanostructured active material formed
thereon.
Based on the above-described mechanism of EDLC, unlike energy
storage in batteries, the process of generating electric double
layer capacitance does not involve a transfer of charge between the
electrodes using electrolyte. While charge in conventional
capacitors is transferred via electrons, capacitance in
double-layer capacitors is related to the moving speed of ions
through the electrolyte and through the resistive porous structure
of the frustules. Since no chemical changes take place within the
electrode or electrolyte, the EDLC can have much higher cycling
lifetimes compared to batteries.
FIG. 15 illustrates a cross-sectional view of a supercapacitor 1500
comprising an electrode that is configured as a pseudo capacitor.
The supercapacitor 1500 may be configured in a similar manner to
the supercapacitor 1400 illustrated above, except for the structure
and the composition of the electrodes. While the supercapacitor
1500 includes a first electrode (not shown), which may be
positively charged in operation, and a second electrode 1550, which
may be negatively charged in operation, only the second electrode
1550 illustrated as a pseudo capacitor is shown for illustration
purposes. The first electrode may be configured as another pseudo
capacitor, or as an EDLC described above. The surface of each of
the first electrode and the second electrode 1550 contacts the
electrolyte 1460. At the contacting interface between the first
electrode and the second electrode 1550 and the electrolyte 1460, a
pseudo capacitance effect arises.
Without being bound to any theory, in operation, applying a voltage
across the first electrode and the second electrode 1550 moves
positive and negative ions in the electrolyte 1460 in opposite
directions towards the first electrode and the second electrode
1550, where electric double layer capacitors may be formed, for
example in a similar manner as described above with respect to
FIGS. 14A, 14B. Pseudocapacitance can arise when ions in the
electrolyte pervade the electric double-layer and become adsorbed
on the electrode surface, as illustrated in FIG. 15. This
pseudocapacitance stores electrical energy by means of reversible
Faradaic redox reactions on the surface the electrode of a
supercapacitor forming an electric double layer described above.
Unlike the electric double layer capacitance effect, the
pseudocapacitance is accompanied with an electron charge-transfer
between the electrolyte 1460 and the adsorbed ions. This Faradaic
charge transfer originates by a very fast sequence of reversible
redox, intercalation or electrosorption processes. The ability of
electrodes to exhibit pseudocapacitance depends on the chemical
affinity of electrode materials to the ions adsorbed on the
electrode surface as well as on the structure and the structure of
the electrode. Materials exhibiting redox behavior for use as
electrodes in pseudo capacitors include transition-metal oxides.
The pseudo capacitance can be expressed as the amount of charge (q)
stored per applied potential (V), or C=dq/dV. Eq. 6
Similar to double layer capacitance, pseudo capacitance or
electrochemical capacitance arises at the surface of the electrode,
e.g., at the surface of surface active materials formed on the
frustules. As a result, the specific surface area is directly
proportional to the number of active sites for the redox reactions,
and hence the magnitude of pseudocapacitance. This Faradaic energy
storage with fast redox reactions makes charging and discharging
much faster than batteries.
Faradaic pseudo capacitance arises in conjunction with static
double-layer capacitance. Depending on the circumstance, its
magnitude may exceed the value of double-layer capacitance for the
same surface area by orders of magnitude, depending on the nature
and the structure of the electrode.
In the following, various aspects of the supercapacitor are
disclosed. While it may not be described in detail, the frustules
according to various embodiments may have any structure and may be
prepared using any method described throughout the application,
including without limitation, FIGS. 1-5X and the associated text.
Various nanostructures including zinc oxide, manganese oxide and
carbon nanostructures according to various embodiments may have any
structure including, e.g., FIG. 5 and may be prepared using any
method described throughout the application, including without
limitation, FIGS. 1-5X and the associated text.
Supercapacitor Electrodes Comprising Frustules Having Formed
Thereon Active Materials
As described above, the interface between the surface active
material of the electrode and the electrolyte provide sites for
energy storage. In the following, various surface active materials
configured to give rise to pseudo capacitance are described. As
described, the surface active material can form a coating on the
frustules, e.g., on the surfaces of the frustules. The coating may
be in the form of nanostructured surface active material, which may
be formed as part of one or more electrodes of the supercapacitor
according to any relevant method, for example described elsewhere
herein.
According to some embodiments, the nanostructured surface active
material formed on frustule surfaces comprises one or more metal
oxides, including, for example, zinc oxide (ZnO), manganese dioxide
(MnO.sub.2), manganese(II, III) oxide (Mn.sub.3O.sub.4),
manganese(II) oxide (MnO), manganese(III) oxide (Mn.sub.2O.sub.3),
mercury oxide (HgO), cadmium oxide (CdO), silver(I,III) oxide
(AgO), silver(I) oxide (Ag.sub.2O), nickel oxide (NiO), lead(II)
oxide (PbO), lead(II, IV) oxide (Pb.sub.2O.sub.3), lead dioxide
(PbO.sub.2), vanadium(V) oxide (V.sub.2O.sub.5), copper oxide
(CuO), molybdenum trioxide (MoO.sub.3), iron(III) oxide
(Fe.sub.2O.sub.3), iron(II) oxide (FeO), iron(II, III) oxide
(Fe.sub.3O.sub.4), rubidium(IV) oxide (RuO.sub.2), titanium dioxide
(TiO.sub.2), iridium(IV) oxide (IrO.sub.2), cobalt(II, III) oxide
(Co.sub.3O.sub.4), tin dioxide (SnO.sub.2), niobium oxide
(Nb.sub.2O.sub.5), combinations thereof, and the like.
According to some embodiments, the nanostructured surface active
material formed on frustule surfaces comprises one or more
metal-containing compounds, including, for example, manganese(III)
oxohydroxide (MnOOH), nickel oxyhydroxide (NiOOH), silver nickel
oxide (AgNiO.sub.2), lead(II) sulfide (PbS), silver lead oxide
(Ag.sub.5Pb.sub.2O.sub.6), bismuth(III) oxide (Bi.sub.2O.sub.3),
silver bismuth oxide (AgBiO.sub.3), silver vanadium oxide
(AgV.sub.2O.sub.5), copper(I) sulfide (CuS), iron disulfide
(FeS.sub.2), iron sulfide (FeS), lead(II) iodide (PbI.sub.2),
nickel sulfide (Ni.sub.3S.sub.2), silver chloride (AgCl), silver
chromium oxide or silver chromate (Ag.sub.2CrO.sub.4), copper(II)
oxide phosphate (Cu.sub.4O(PO.sub.4).sub.2), lithium cobalt oxide
(LiCoO.sub.2), metal hydride alloys (e.g., LaCePrNdNiCoMnAl),
lithium iron phosphate (LiFePO.sub.4 or LFP), lithium permanganate
(LiMn.sub.2O.sub.4), lithium manganese dioxide (LiMnO.sub.2),
Li(NiMnCo)O.sub.2, Li(NiCoAl)O.sub.2, cobalt oxyhydroxide (CoOOH),
titanium nitride (TiN), combinations thereof, and the like.
According to some embodiments, the nanostructured surface active
material formed on frustule surfaces comprises mixed transition
metal spinels and binary metal oxides, including, for example,
MnFe.sub.2O.sub.4, NiCo.sub.2O.sub.4, CuCo.sub.2O.sub.4,
ZnCo.sub.2O.sub.4, Zn.sub.2SNO.sub.4, NiMoO.sub.4, combinations
thereof, and the like.
According to some embodiments, the nanostructured surface active
material formed on frustule surfaces comprises metal hydroxides,
including, for example, Ni(OH).sub.2, Co(OH).sub.2,
H.sub.2Ti.sub.3O.sub.7, combinations thereof, and the like.
According to other embodiments, the nanostructured surface active
material formed on frustule surfaces comprises a mixture of any of
the above materials. By way of example, combinations of material
that can coat the frustules include, for example,
MnxO.sub.y--Co.sub.xO.sub.y, MnO.sub.2--NiO/Ni(OH).sub.2,
Mn.sub.xO.sub.y--TiO.sub.2 and Mn.sub.xO.sub.y--ZnO, to name a
few.
In addition to the surface active material that forms the interface
with the electrolyte to provide sites for energy storage, the
electrode of supercapacitors also includes electrically conducting
materials. In addition to providing electrical conductivity to the
frustules, which may be electrically insulating, to enable the
electric double layer capacitance or the pseudo capacitance
described above, the electrically conducting material may lower the
internal resistance, for higher power, as described above. One or
more of the above compounds can be coated on the frustules with one
or more electrically conducting materials. The electrically
conducting material may be carbon-based in some implementations.
For example, the electrically conducting material may comprise one
or more of various carbon compounds, e.g., graphene, graphite,
carbon nanotubes (CNTs), fullerenes, carbon nanofibers and/or
carbon aerogels, to name a few.
The electrically conducting material may be metal-based in some
implementations. For example, the electrically conducting material
may comprise a metallic element or compound, e.g., Ag, Au,
stainless steel, Mn, Cu, Ni and/or Al to name a few. In some
implementations, the electrically conducting material may comprise
a conducting polymer, e.g., polyaniline (PANI),
poly(3,4-ethylenedioxythiophene) (PEDOT), polypyrrole and/or
related polymers, to name a few.
While various embodiments are described in which the surface active
material and the electrically conducting material may be formed on
surfaces of each of the frustules, not all embodiments necessarily
include such features. In some embodiments, herein and throughout
the entire application, the surface active material and the
electrically conducting material may be formed, in addition to or
in lieu of being formed on the surfaces of each of the frustules,
on or over a layer of frustules or between the frustules within a
layer of frustules.
While various embodiments are described in which the active
material is nanostructured, not all embodiments necessarily include
such features. In some embodiments, herein and throughout the
entire application, the surface active material may form a
continuous or contiguous network of a thin film of the surface
active material.
Supercapacitor Electrodes Comprising Frustules Having Formed
Thereon Manganese Oxide as Surface Active Material
An surface active material for a supercapacitor electrode, e.g., an
electrode configured to give rise to pseudo capacitance, may
include one or more manganese-containing compounds, e.g., a
manganese oxide, described above. The manganese-containing compound
may have a composition and be prepared using any relevant method,
for example as described herein. According to some embodiments, one
or more electrodes comprise frustules having formed thereon a
manganese oxide (Mn.sub.xO.sub.y), e.g., manganese oxide
nanostructures, as the surface active material. In some
embodiments, the frustules have surfaces that are coated with
manganese oxide nanostructures in any manner described herein.
Frustules coated with manganese oxide, e.g., manganese oxide
nanoparticles, may constitute about 50-95 wt. %, 55-85 wt. %, 60-80
wt. %, 65-75 wt. %, or a value in a range defined by any of these
values, for instance about 70 wt. %, on the basis of the total
weight of the electrode, e.g., as printed and dried.
The one or more electrodes comprising manganese oxide can
additionally comprise an electrically conducting material as
described above. The electrically conducting material can include,
e.g., conductive carbon in the amount of about 0.1-15 wt. %, 1-13
wt. %, 3-11 wt. %, 5-9 wt. %, 6-8 wt. %, for instance about 7 wt.
%, on the basis of the total weight of the electrode, e.g., as
printed and dried. The conductive carbon forms part of the
electrode to provide electrical conductivity as described above.
The conductive carbon can improve printability of inks. The
conductive carbon can increase flexibility of the resulting
supercapacitor. One example of conductive carbon that can be
included as part of the one or more electrodes is Timcal Super
65.RTM., sold by Timcal Graphite & Carbon (Switzerland).
The one or more electrodes comprising manganese oxide can
additionally comprise carbon nanotubes in the amount of about
0.1-15 wt. %, 1-13 wt. %, 3-11 wt. %, 5-9 wt. %, 6-8 wt. %, for
instance about 7 wt. %, on the basis of the total weight of the
electrode, e.g., as printed and dried. The carbon nanotubes serve
as part of the electrode to provide electrical conductivity. The
carbon nanotubes can improve printability of inks. The carbon
nanotubes can increase flexibility of the resulting supercapacitor.
One example of carbon nanotubes that can be included as part of the
one or more electrodes is multiwalled carbon nanotubes, sold by
Cheap Tubes Inc. (United States).
The one or more electrodes comprising manganese oxide can
additionally comprise a polymer binder in the amount of about
0.1-15 wt. %, 0.5-12 wt. %, 1-9 wt. %, 2-6 wt. %, 3-5 wt. %, for
instance about 4 wt. %, on the basis of the total weight of the
electrode, e.g., as printed and dried. The polymer binder promotes
adhesion to substrates and other layers and integrity of the layers
(e.g., hold particles together). One example of polymer binder that
can be included as part of the one or more electrodes is
polyvinylidene fluoride (PVDF), sold by Solef 5130 (Belgium).
[0469] The one or more electrodes comprising manganese oxide can
additionally comprise an electrolyte comprising an ionic liquid.
The ionic liquid may be present in the amount of about 5-30 wt. %,
8-27 wt. %, 11-24 wt. %, 14-21 wt. %, 17-20 wt. %, for instance
about 18 wt. %, on the basis of the total weight of the electrode,
e.g., as printed and dried. The ionic liquid can serve as an
electrolyte or be part of an electrolyte. One example of ionic
liquid that can be included as part of the one or more electrodes
is 1-ethyl-3-methylimidazolium tetrafluoroborate
(C.sub.2mimBF.sub.4), sold by IoLitec (Germany).
The one or more electrodes comprising manganese oxide can
additionally comprise a salt, which may be dissolved in the solvent
or the ionic liquid in the amount of about 0.1-5 wt. %, 1-5 wt. %,
1.5-4.5 wt. %, 2.0-4.0 wt. %, 2.5-3.5 wt. %, for instance about 3
wt. %, on the basis of the total weight of the electrode, e.g., as
printed and dried. The salt serves as an additive to improve ionic
conductivity. The salt can promote higher capacitance by
contributing to interface structure. One example of ionic liquid
that can be included as part of the one or more electrodes is
1-ethyl-3-methylimidazolium tetrafluoroborate (C.sub.2mimBF.sub.4),
sold by IoLitec (Germany). The salt and the ionic liquid that can
be included as part of the one or more electrodes can be any salt
or any ionic liquid described herein.
In some embodiments, in addition to an ionic liquid or a
combination of an ionic liquid and a salt, the one or more
electrodes comprising manganese oxide may comprise a solvent of the
electrolyte that may be residual after drying.
In some embodiments, the one or more electrodes comprise a gel that
serves as a medium for ion transportation. The gel can include the
electrolyte, which can include one or more of a solvent, salt and
an ionic liquid, and a suitable gel-forming or a gelling polymer,
as described herein.
In some embodiments, the gel can at least partially fill the
network of pores in the frustules. When the gel substantially
entirely fills the network of pores, the resulting electrode may be
substantially free of pores comprising voids. On the other hand,
when the gel partially fills the network of pores, the resulting
separator may still include some pores comprising voids. The voids,
when present, may be filled with the electrolyte.
In some configurations, once it fills the network of pores in the
frustules, the gel including the electrolyte may remain relatively
localized without freely moving through the network of pores in the
frustules.
Supercapacitor Electrodes Comprising Frustules and Zine Oxide as
Surface Active Material
An active material for a supercapacitor electrode, e.g., an
electrode configured to give rise to pseudo capacitance, includes
one or more zinc-containing compounds, e.g., a zinc oxide,
described above. The zinc-containing compound may have a
composition and be prepared using any relevant method described
herein. According to some embodiments, one or more electrodes
comprise frustules having formed thereon a zinc oxide
(Zn.sub.xO.sub.y, e.g., ZnO), e.g., zinc oxide nanostructures, as
the surface active material. In some embodiments, the frustules
have surfaces that are coated with zinc oxide nanostructures in any
manner described herein. Frustules coated with zinc oxide, e.g.,
zinc oxide nanoparticles, can constitute about 25-90 wt. %, 30-80
wt. %, 35-70 wt. %, 40-60 wt. %, 45-50 wt. % or a value in a range
defined by any of these values, for instance about 46 wt. %, on the
basis of the total weight of the electrode, e.g., as printed and
dried.
The one or more electrodes comprising zinc oxide can additionally
comprise an electrically conducting material as described above.
The electrically conducting material can include, e.g., conductive
carbon in the amount of about 0.1-15 wt. %, 2-14 wt. %, 4-13 wt. %,
6-12 wt. %, 8-11 wt. %, for instance about 10 wt. %, on the basis
of the total weight of the electrode, e.g., as printed and dried.
The conductive carbon can form part of the electrode to provide
electrical conductivity. The conductive carbon can improve
printability of inks. The conductive carbon can increase
flexibility of the resulting supercapacitor. The conductive carbon
can serve as part of the electrode to provide electrical
conductivity as described above. The conductive carbon can improve
printability of inks. The conductive carbon can increase
flexibility of the resulting supercapacitor. One example of
conductive carbon that can be included as part of the one or more
electrodes is Timcal Super 65.RTM., sold by Timcal Graphite &
Carbon (Switzerland).
The one or more electrodes comprising zinc oxide can additionally
comprise carbon nanotubes in the amount of about 0.1-15 wt. %,
0.1-11 wt. %, 0.1-7 wt. %, 0.1-5 wt. %, 1-3 wt. %, for instance
about 2 wt. %, on the basis of the total weight of the electrode,
e.g., as printed and dried. The carbon nanotubes can serve as part
of the electrode to provide electrical conductivity. The carbon
nanotubes can improve printability of inks. The carbon nanotubes
can increase flexibility of the resulting supercapacitor. One
example of carbon nanotubes that can be included as part of the one
or more electrodes is multi-walled carbon nanotubes, sold by Cheap
Tubes Inc. (United States).
The one or more electrodes comprising zinc oxide can additionally
comprise a polymer binder in the amount of about 0.1-15 wt. %,
0.5-13 wt. %, 1-11 wt. %, 2-9 wt. %, 3-7 wt. %, for instance about
5 wt. %, on the basis of the total weight of the electrode, e.g.,
as printed and dried. The polymer binder can promote adhesion to
substrates and other layers and integrity of the layers (e.g., hold
particles together). One example of polymer binder that can be
included as part of the one or more electrodes is polyvinylidene
fluoride (PVDF), sold by Solef 5130 (Belgium).
The one or more electrodes comprising zinc oxide can additionally
comprise an electrolyte comprising an ionic liquid. The ionic
liquid may be present in the amount of about 10-50 wt. %, 15-50 wt.
%, 20-45 wt. %, 25-40 wt. %, 30-35 wt. %, for instance about 34 wt.
%, on the basis of the total weight of the electrode, e.g., as
printed and dried. The ionic liquid can serve as an electrolyte or
be part of an electrolyte. One example of ionic liquids that can be
included as part of the one or more electrodes is
1-ethyl-3-methylimidazolium tetrafluoroborate (C.sub.2mimBF.sub.4),
sold by IoLitec (Germany).
The one or more electrodes comprising zinc oxide can additionally
comprise a salt, which may be dissolved in the ionic liquid in the
amount of about 0.1-5 wt. %, 1-5 wt. %, 1.5-4.5 wt. %, 2.0-4.0 wt.
%, 2.5-3.5 wt. %, for instance about 3 wt. %, on the basis of the
total weight of the electrode, e.g., as printed and dried. The salt
can serve as an additive to improve ionic conductivity. The salt
can promote higher capacitance by contributing to interface
structure. One example of ionic liquids that can be included as
part of the one or more electrodes is 1-ethyl-3-methylimidazolium
tetrafluoroborate (C.sub.2mimBF.sub.4), sold by IoLitec
(Germany).
In some embodiments, in addition to an ionic liquid or a
combination of an ionic liquid and a salt, the one or more
electrodes comprising zinc oxide may comprise a solvent of the
electrolyte that may be residual after drying.
Supercapacitor Electrodes Comprising Frustules Having Formed
Thereon Carbon Nanostructures as Surface Active Material
An active material for a supercapacitor electrode, e.g., an
electrode configured to give rise to EDCL, includes one or more
carbon nanostructures, e.g., CNT as described above. The carbon
nanostructures may have a composition and be prepared using any
relevant method described herein. According to some embodiments,
one or more electrodes comprise frustules having formed thereon
carbon structures, e.g., carbon nanostructures, as the surface
active material. In some embodiments, the frustules have surfaces
that are coated with carbon nanostructures, e.g., CNTs, in any
manner described above. The one or more electrodes comprise CNTs in
the amount of about 1-50 wt. %, 1-40 wt. %, 1-30 wt. %, 1-20 wt. %,
5-15 wt. %, for instance about 11 wt. %, on the basis of the total
weight of the electrode, e.g., as printed and dried. The carbon
nanotubes can serve as part of the surface active material. The
carbon nanotubes can provide printability of inks. The carbon
nanotubes can increase flexibility of the resulting supercapacitor.
One example of carbon nanotubes that can be included as part of the
one or more electrodes is multiwall carbon nanotubes, sold by Cheap
Tubes Inc. (United States).
The one or more electrodes comprising carbon can additionally
comprise an electrically conducting material as described above.
The electrically conducting material can include, e.g., conductive
carbon in the amount of about 1-50 wt. %, 1-40 wt. %, 1-30 wt. %,
1-20 wt. %, 5-15 wt. %, for instance about 11 wt. %, on the basis
of the total weight of the electrode, e.g., as printed and dried.
The conductive carbon can form part of the surface active material.
The conductive carbon can provide printability of inks. The
conductive carbon can increase flexibility of the resulting
supercapacitor. One example of conductive carbon that can be
included as part of the one or more electrodes is Timcal Super
65.RTM., sold by Timcal Graphite & Carbon (Switzerland).
The one or more electrodes comprising CNTs can additionally
comprise polymer binder in the amount of about 0.1-15 wt. %, 1-13
wt. %, 3-11 wt. %, 5-9 wt. %, for instance about 7 wt. %, on the
basis of the total weight of the electrode, e.g., as printed and
dried. The polymer binder can promote adhesion to substrates and
other layers and integrity of the layers (e.g., hold particles
together). One example of polymer binder that can be included as
part of the one or more electrodes is polyvinylidene fluoride
(PVDF), sold by Solef 5130 (Belgium).
The one or more electrodes comprising CNTs can additionally
comprise ionic liquid in the amount of about 10-90 wt. %, 30-85 wt.
%, 50-80 wt. %, 70-75 wt. %, for instance about 71 wt. %, on the
basis of the total weight of the electrode, e.g., as printed and
dried. The ionic liquid can serve as an electrolyte or be part of
an electrolyte. One example of ionic liquids that can be included
as part of the one or more electrodes is
1-ethyl-3-methylimidazolium tetrafluoroborate (C.sub.2mimBF.sub.4),
sold by IoLitec (Germany).
The one or more electrodes comprising CNTs can additionally
comprise a salt, which may be dissolved in the ionic liquid in the
amount of about 0.1-5 wt. %, 1-5 wt. %, 1.5-4.5 wt. %, 2.0-4.0 wt.
%, 2.5-3.5 wt. %, for instance about 3 wt. %, on the basis of the
total weight of the electrode, e.g., as printed and dried. The salt
can serve as an additive to improve ionic conductivity. The salt
can promote higher capacitance by contributing to interface
structure. One example of ionic liquids that can be included as
part of the one or more electrodes is 1-ethyl-3-methylimidazolium
tetrafluoroborate (C.sub.2mimBF.sub.4), sold by IoLitec (Germany).
The salt and the ionic liquid that can be included as part of the
one or more electrodes can be any salt or any ionic liquid
described herein.
In some embodiments, in addition to an ionic liquid or a
combination of an ionic liquid and a salt, the one or more
electrodes comprising CNT may comprise a solvent of the electrolyte
that may be residual after drying.
Supercapacitor Separators
According to various embodiments, supercapacitors further comprise
a separator. The separator, which may be interposed between the
electrodes, can inhibit or prevent an electrical short that may
result from a direct contact between the electrodes. The separator
may include frustules. The separator may be configured to serve as
a permeable membrane for ion transportation. Frustule-containing
separators can provide lower electrical resistance, chemical
stability and/or relatively small thickness. The frustules serve as
a separator filler material and to improve printability, e.g., by
inhibiting or preventing holes from forming during printing,
thereby shorting the electrodes.
Frustule-containing separators can have any structure and
composition, and can be prepared using any method described
herein.
Referring to FIGS. 14A, 14B and 15, each of the supercapacitors
1400, 1500 comprises a separator 1430 comprising frustules, e.g.,
purified frustules that constitute about 10-70 wt. %, 13-55 wt. %,
16-45 wt. %, 19-35 wt. %, 20-25 wt. % or a value in a range defined
by any of these values, for instance about 22 wt. %, on the basis
of the total weight of the separator, e.g., as printed and dried.
Various characteristics and processes of forming purified frustules
and a separator therefrom are described above.
The separator 1430 comprising frustules can additionally comprise a
thermally conductive additive in the amount of about 0.1-5 wt. %,
0.5-4 wt. %, 1-3 wt. %, 1.5-2.5 wt. %, for instance about 2 wt. %,
on the basis of the total weight of the separator, e.g., as printed
and dried. The thermally conductive additive may serve as a
separator filler. The thermally conductive additive may serve as a
heat absorbing and/or conducting agent, e.g., as a near infrared
radiation (NIR) absorbing agent. As described herein, a NIR
radiation may have a wavelength of 0.7 .mu.m to 2.5 mm. The
thermally conducive additive may efficiently absorb and/or conduct
heat during fabrication, e.g., during a drying process using near
infrared radiation (NIR). The thermally conductive additive may
reduce the internal resistance of the supercapacitor, thereby
improving the power. The thermally conductive additive may, e.g.,
be a good heat absorber, a good thermal conductor and a relatively
good electrical insulator. One example of such thermally conductive
additives that can be included as part of the separator is graphene
oxide (GO), sold by Cheap Tubes Inc. (U.S.A). The inventors have
found that, when graphene oxide is added to the ink for printing
the separator, the resulting ink showed improved printability,
superior heat conduction during drying (which reduces drying time)
and relatively lower internal resistance of the supercapacitor,
although not all such advantages are necessary. In addition,
because the thermally conductive additive such as GO can be a good
electrical insulator, the separator advantageously maintains the
electrically insulating characteristics. In some embodiments, GO
comprises sheets of GO that contact each other to form a network of
contiguous GO sheets. The inventors have found, when included as
part of a printed layer such as a printed separator layer, GO may
reduce the drying time by as much as one order of magnitude, e.g.,
from tens or minutes to tens of seconds.
The separator comprising frustules can additionally comprise a
polymer binder in the amount of about 5-20 wt. %, 5-15 wt. %, 5-10
wt. %, 6-8 wt. %, for instance about 7 wt. %, on the basis of the
total weight of the separator, e.g., as printed and dried. The
polymer binder can promotes adhesion to substrates and other layers
and integrity of the layers (e.g., hold particles together). One
example of polymer binder that can be included as part of the
separator is polyvinylidene fluoride (PVDF), sold by Solef 5130
(Belgium).
The separator comprising frustules can additionally comprise a
gelling polymer in the amount of about 0.5-10 wt. %, 1.0-7.0 wt. %,
1.5-5.0 wt. %, 2.0-4.0 wt. %, for instance about 3 wt. %, on the
basis of the total weight of the separator, e.g., as printed and
dried. The gelling polymer may form a gel with an ionic liquid. One
example of the gelling polymer that can be included as part of the
separator is polyethylene glycol, sold by Sigma Aldrich
(U.S.A.).
In some embodiments, the gelling polymer forms gel that serves as a
medium for ion transportation. The gel can fill the network of
pores in the frustules. The gel can include the electrolyte, which
can include one or more of a solvent, salt and an ionic liquid, and
a suitable gel-forming or a gelling polymer, as described
herein.
In some embodiments, the gel can at least partially fill the
network of pores in the frustules. When the gel substantially
entirely fills the network of pores, the resulting separator may be
substantially free of pores comprising voids. Advantageously, the
separator that is substantially free of pores can be effective in
preventing undesirable movement of particles therethrough, which
may be particularly advantageous in the context of printed layers
having various components, e.g., frustules and/or nanostructures,
that can become loose and separated.
On the other hand, when the gel partially fills the network of
pores, the resulting separator may still include some pores
comprising voids, which may be filled with electrolyte.
Advantageously, such configuration may increase ionic conductivity
for higher power.
In some configurations, once it fills the network of pores in the
frustules, the gel including the electrolyte may remain relatively
localized without freely moving through the network of pores in the
frustules.
The separator comprising frustules can additionally comprise an
electrolyte, which may include an ionic liquid. The ionic liquid
may be present in the amount of about 10-80 wt. %, 30-75 wt. %,
50-70 wt. %, 55-65 wt. %, for instance about 60 wt. %, on the basis
of the total weight of the separator, e.g., as printed and dried.
The ionic liquid can serve as an electrolyte or be part of an
electrolyte. One example of ionic liquid that can be included as
part of the separator is 1-ethyl-3-methylimidazolium
tetrafluoroborate (C.sub.2mimBF.sub.4), sold by IoLitec
(Germany).
The separator comprising frustules can additionally comprise a
salt, which may be dissolved in the electrolyte, in the amount of
about 0.1-8 wt. %, 1-7.5 wt. %, 3.0-7.0 wt. %, 5.0-6.5 wt. %,
5.5-6.5 wt. %, for instance about 6 wt. %, on the basis of the
total weight of the separator, e.g., as printed and dried. The salt
can serve as an additive to improve ionic conductivity. The salt
can promote higher capacitance by contributing to interface
structure. One example of the salt that can be included as part of
the one or more electrodes is zinc tetrafluoroborate
Zn(BF.sub.4).sub.2, sold by Sigma Aldrich (U.S.A).
As described above, various components including one or more of the
electrodes and the separator of the supercapacitor may
advantageously be printed using a ink. In the following,
compositions of inks that can be used to print the one or more of
the electrodes and the separator are described.
Advantageously, when printed, the thicknesses of each of the
electrodes and the separator can be made extremely thin. Each of
the separator and the electrodes can have a thickness of 10-50
microns, 50-100 microns, 100-200 microns, 200-300 microns, 300-400
microns, 400-500 microns, or a thickness in a range defined by any
of these values.
Composition and Method of Preparing Printable Manganese
Oxide-Containing Ink for Supercapacitor Electrodes
As described above, one of the possible advantages of the
supercapacitors described herein includes the relative ease and
lower cost of manufacturing, arising from printability of one or
more layers of the supercapacitors, including the electrodes.
According to various embodiments, a manganese oxide-containing ink
that can be used to form one or more electrodes of the
supercapacitor can include any component or composition, and may be
prepared using any method of preparing Mn.sub.xO.sub.y-based inks
described elsewhere herein. In some embodiments, prior to printing
and drying, the manganese oxide-containing ink includes various
components of the manganese oxide-containing electrode described
above in the amount of about 20-70 wt. %, 25-60 wt. %, 30-50 wt. %,
30-40 wt. %, or a value in a range defined by any of these values,
for instance about 34 wt. %, on the basis of the total weight of
the manganese oxide-containing ink.
Prior to printing and drying, the manganese oxide-containing ink
includes a solvent, which may constitute the balance of the
manganese oxide-containing ink. The manganese oxide-containing ink
includes the solvent in the amount of about 30-80 wt. %, 40-75 wt.
%, 50-70 wt. %, 60-70 wt. %, or a value in a range defined by any
of these values, for instance about 66 wt. %, on the basis of the
total weight of the manganese oxide-containing ink. One example
solvent is n-methylpyrrolidone.
The manganese oxide-containing ink may be prepared according to the
following example method. A solvent, an ionic liquid and carbon
nanotubes (CNTs) are mixed, e.g., in a vial, and the resulting
mixture may be sonicated, e.g., for 1-15 min., to disperse the
CNTs. The manganese oxide-coated frustules are added, and the
mixture may be stirred, e.g., for 5-30 min. at 50-150.degree. C. on
a hot plate. The mixture may be further mixed in a planetary
centrifugal mixer (for example, THINKY, USA) for 1-10 min. at
500-2000 rpm. Conductive carbon can be added and mixed next,
followed by lab egg mixing for 1-15 min. at 150.degree. C.
Subsequently, a polymer, which may be dissolved in or mixed with a
solvent, can be added, and the mixture can be stirred with lab egg
stirrer with heat for 5-30 min. on a hot plate at 50-150.degree. C.
The mixture can be further mixed, e.g., on a hot plate and/or on a
planetary centrifugal mixer for 1-15 min. at 500-2000 rpm.
Composition and Method of Preparing Printable Zinc Oxide-Containing
Ink for Supercapacitor Electrodes
According to various embodiments, a zinc oxide-containing ink that
can be used to form one or more electrodes of the supercapacitor
can include any component or composition, and be prepared using any
method of preparing ZnO-based inks described herein. In some
embodiments, prior to printing and drying, the zinc
oxide-containing ink includes various components of the zinc
oxide-containing electrode described above in the amount of about
20-70 wt. %, 25-60 wt. %, 25-50 wt. %, 25-40 wt. %, or a value in a
range defined by any of these values, for instance about 29 wt. %,
on the basis of the total weight of the zinc oxide-containing
ink.
Prior to printing and drying, the zinc oxide-containing ink
includes a solvent, which may constitute the balance of the zinc
oxide-containing ink. The zinc oxide-containing ink can include the
solvent in the amount, of about 30-80 wt. %, 40-75 wt. %, 50-75 wt.
%, 60-75 wt. %, or a value in a range defined by any of these
values, for instance about 71 wt. %, on the basis of the total
weight of the zinc oxide-containing ink. One example of a solvent
includes n-methylpyrrolidone.
The zinc oxide-containing ink may be prepared according to the
following example method. A solvent, an ionic liquid and carbon
nanotubes (CNTs) are mixed, e.g., in a vial, and the resulting
mixture may be sonicated, e.g., for 1-15 min., to disperse the
CNTs. The zinc oxide-coated diatoms are added and the mixture is
stirred, e.g., for 1-15 min. at 50-150.degree. C. on a hot plate,
and mixed, e.g., on a planetary centrifugal mixer for 1-15 min. at
500-2000 rpm. Conductive carbon can be added and mixed next, for
1-15 min. on the hotplate at 50-150.degree. C. Subsequently, a
polymer, which may be dissolved in or mixed with a solvent, can be
added, and the mixture is stirred for 1-15 min. at 50-150.degree.
C. The mixture can be further mixed, e.g., on a hot plate and/or on
a planetary centrifugal mixer for 1-15 min. at 500-2000 rpm.
Composition and Method of Preparing Printable Carbon
Nanotube-Containing Ink for Supercapacitor Electrodes
According to various embodiments, a carbon nanotube
(CNT)-containing ink that can be used to form one or more
electrodes of the supercapacitor can include any component or
composition, and be prepared using any method of preparing
CNT-based inks described herein. In some embodiments, prior to
printing and drying, the CNT-containing ink can include various
components of the CNT-containing electrode described above in the
amount of about 10-80 wt. %, 10-60 wt. %, 10-40 wt. %, 10-30 wt. %,
or a value in a range defined by any of these values, for instance
about 18 wt. %, on the basis of the total weight of the
CNT-containing ink.
Prior to printing and drying, the CNT-containing ink can include a
solvent, which may constitute the balance of the CNT-containing
ink. The CNT-containing ink can include the solvent in the amount
of about 10-80 wt. %, 10-60 wt. %, 10-40 wt. %, 10-30 wt. %, or a
value in a range defined by any of these values, for instance about
18 wt. %, on the basis of the total weight of the CNT-containing
ink. One example of a solvent includes n-methylpyrrolidone.
The CNT-containing ink may be prepared according to the following
one example method. Solvent, ionic liquid and CNTs are mixed
together, e.g., in a vial. The resulting mixture may be sonicated
for 1-15 min. to disperse the CNTs. Conductive carbon may
subsequently be added and mixed, e.g., for 1-15 min. on the
hotplate at 50-150.degree. C. Subsequently, a polymer, which may be
dissolved in or mixed with a solvent, may be added and the mixture
may be stirred, e.g., for 1-15 min at 50-150.degree. C. on a hot
plate. The mixture can be further mixed on a planetary centrifugal
mixer for 1-15 min. at 500-2000 rpm.
Composition and Method of Preparing Printable Frustule-Containing
Ink for Supercapacitor Separators
According to various embodiments, a frustule-containing ink that
can be used to form a separator of the supercapacitor can include
any component or composition, and can be prepared using any method
of preparing frustule-based inks described herein. In some
embodiments, prior to printing and drying, the frustule-containing
ink includes various components of the frustule-containing
electrode described above in the amount of about 20-80 wt. %, 30-70
wt. %, 40-60 wt. %, 50-60 wt. %, or a value in a range defined by
any of these values, for instance about 54 wt. %, on the basis of
the total weight of the frustule-containing ink.
Prior to printing and drying, the frustule-containing ink includes
a solvent, which may constitute the balance of the
frustule-containing ink. The frustule-containing ink can include
the solvent in the amount, of about 20-80 wt. %, 30-70 wt. %, 40-60
wt. %, 40-50 wt. %, or a value in a range defined by any of these
values, for instance about 46 wt. %, on the basis of the total
weight of the frustule-containing ink. One example solvent is
tetramethyl urea.
The frustule-containing ink may be prepared according to the
following example method. A gelling polymer and a binder polymer
are dissolved in a solvent, e.g., at 50-150.degree. C. on a hot
plate. Graphene oxide may be mixed with an electrolyte and a
solvent. The graphene oxide mixture may be sonicated for 1-15 min.
and mixed with the dissolved polymers. Subsequently, the purified
diatoms are added and the mixture may be stirred at 50-150.degree.
C. on the hot plate for 5-60 min.
Example Components of Printable Inks for Supercapacitor Electrodes
and/or Separators
Printable inks for printing one or more layers of a supercapacitor,
e.g., electrode and/or separator layers, can include purified
diatom frustules, which may have any structure and composition and
be prepared using any method as described herein. According to some
embodiments, the purified diatom frustules may be substantially
unmodified (e.g., the chemical composition of purified diatom
frustules may have substantially the same composition as the
frustules in natural form).
Printable inks for printing one or more electrode layers, e.g.,
electrode layers configured as a pseudo capacitor, can comprise
diatom frustules coated with a zinc oxide (ZnO), diatom frustules
coated with a manganese oxide (Mn.sub.xO.sub.y including, e.g.,
MnO, Mn.sub.2O.sub.3, Mn.sub.3O.sub.4, MnOOH and MnO.sub.2 and
their mixtures), which may have any component, composition and be
prepared using any method as described herein.
Printable inks for printing one or more electrode layers, e.g.,
electrode layers configured as a pseudo capacitor or as an EDLC,
can comprise diatom frustules coated with carbon nanotubes (CNTs),
which may include any component or composition, and be prepared
using any preparation method described herein. For example, CNTs
included in the inks may include one or more of any of a variety of
forms of CNTs, including multi wall, single wall, double wall,
metallic and semiconducting, among other forms of CNTs.
Printable inks for printing one or more electrode layers, e.g.,
electrode layers configured as a pseudo capacitor or as an EDLC,
can comprise one or more conductive carbon, which may include any
component or composition and be prepared using any preparation
method described herein. For example, conductive carbon included in
the inks may include one or more of graphene, graphite, carbon
nano-onions, carbon black, carbon fibers, carbon nanofibers,
amorphous carbon, activated carbon, charcoal, carbon buckyballs,
carbon nanobuds, and pyrolytic carbon, among other forms of
conductive carbon.
Printable inks for printing a separator can comprise one or more
thermally conductive additives, e.g., graphene oxide. As described
herein, graphite is a three-dimensional carbon based material made
up of millions of layers of graphene, as understood in the relevant
industry. Graphite oxide refers to a material formed by oxidation
of graphite using strong oxidizing agents, thereby introducing
oxygenated functionalities to graphite. For example, graphite oxide
may expand the layer separation, or make the material hydrophilic.
Graphite oxide can be exfoliated, e.g., in water using sonication,
thereby producing a two-dimensional material comprising a single or
a few layers of graphite oxide, which is referred to in the
industry and herein a graphene oxide (GO). According to various
embodiments described herein, GO refers to a structure having one
or more layers but fewer than about 100, 50, 20, 10 or 5 sheets,
any number of sheets within a range defined by any of these
values.
According to various embodiments, GO can have a carbon-to-oxide
ratio between about 1 to 100, 1 to 2, 2 to 5, 5 to 10, 10 to 15, 15
to 20, 20 to 25, 25 to 30, 30 to 35, 35 to 40, 40 to 45, 45 to 50,
50 to 55, 55 to 60, 60 to 65, 65 to 70, 70 to 75, 75 to 80, 80 to
85, 85 to 90, 90 to 95, 95 to 100, or a ratio within a range
defined by any of these values. For instance, according to some
embodiments, GO sheets have a mean carbon-to-oxygen ratio of about
2:1 to about 20:1 or about 5:1 to about 20:1.
Other embodiments of thermally conductive additives are possible.
For example, the conductive additives can include one or more of
boron nitride, beryllium oxide and other thermally conductive
dielectric materials.
Various materials included in the inks for forming the layers of
the supercapacitor, including coated diatoms, CNTs, conductive
carbons, thermally conductive additives can have particle size
ranging from 1 nm to 100 microns.
Printable inks for printing one or more layers of a supercapacitor,
e.g., an electrode and/or a separator layers, can include a binder.
The binder can include any component and composition of binders in
the inks and electrodes as described herein. Examples of binders
that can be used include styrene butadiene rubber (SBR), polyvinyl
pyrrolidone (PVP), polyvinylidene fluoride, polyvynylidene
fluoride-trifluoroethylene, polytetrafluoroethylene,
polydimethylsiloxane, polyethelene, polypropylene, polyethylene
oxide, polypropylene oxide, polyethylene glycolhexafluoropropylene,
polyethylene terefphtalatpolyacrylonitryle, polyvinyl butyral,
polyvinylcaprolactam, polyvinyl chloride; polyimide polymers and
copolymers (including aliphatic, aromatic and semi-aromatic
polyimides), polyamides, polyacrylamide, acrylate and
(meth)acrylate polymers and copolymers such as
polymethylmethacrylate, polyacrylonitrile, acrylonitrile butadiene
styrene, allylmethacrylate, polystyrene, polybutadiene,
polybutylene terephthalate, polycarbonate, polychloroprene,
polyethersulfone, nylon, styrene-acrylonitrile resin; polyethylene
glycols, clays such as hectorite clays, garamite clays,
organomodified clays; saccharides and polysaccharides such as guar
gum, xanthan gum, starch, butyl rubber, agarose, pectin; celluloses
and modified celluloses such as hydroxyl methylcellulose,
methylcellulose, ethyl cellulose, propyl methylcellulose, methoxy
cellulose, methoxy methylcellulose, methoxy propyl methylcellulose,
hydroxy propyl methylcellulose, carboxy methylcellulose, hydroxy
ethylcellulose, ethyl hydroxyl ethylcellulose, cellulose ether,
cellulose ethyl ether, chitosan as well as their polymeric
precursors or polymerizable precursors.
Printable inks for printing one or more layers of a supercapacitor,
e.g., electrode and/or separator layers, can include a gelling
polymer. The gelling polymer can include any component and
composition of gelling polymers in the inks and electrodes as
described herein. Examples of gelling polymers that can be used
include polyvinylidene fluoride, polyacrylic acid, polyethylene
oxide, polyvinyl alcohol.
According to various embodiments, all polymers included in the inks
have suitable chemical, thermal and electrochemical stability such
that they can be formed into printed layers.
Electrolytes for Supercapacitors
The energy density (E) of supercapacitors can be expressed as
E=CV.sup.2/2, Eq. 7 where C is the capacitance and V is the
voltage. The voltage to which supercapacitors can be charged
depends on, among other things, the electrochemical potential
window of the electrolyte. Because of the strong dependence of
energy density on voltage (proportional to square root of voltage),
the electrochemical potential windows of electrolytes can have a
substantial impact on the energy density, sometimes a larger impact
on the energy density than the capacitance.
Operating electrochemical potential windows of typical aqueous
electrolytes is 1-1.3V (hydrogen/oxygen evolution occur if one
exceeds this voltage). Organic based electrolytes can have
potential windows of 2.5-2.7V. To obtain significantly higher
potential windows, e.g., 3.5-4.5V or even higher, electrolytes
according to some embodiments include ionic liquids.
According to various embodiments, the electrolytes included in the
supercapacitors have wide electrochemical potential window (for
higher energy density), have higher ionic conductivity (low
resistance and higher power), have higher chemical stability to
other components, have wide temperature operating range, have low
volatility and flammability, are environmentally friendly and/or
are lower in cost, among other possible advantages.
As described herein, an electrolyte includes an electrolyte salt
(or acid, base) and a solvent. The solvent can be aqueous or
organic. Advantageously, solvents can have relatively high boiling
point (above 80.degree. C.). The solvents according to embodiments
also have relatively slow evaporation rate to reduce solvent loss
during ink mixing and printing as well as influencing the ink shelf
life. The slow evaporation rate also increases lifetime of the
supercapacitor. The solvents may be selected to dissolve various
polymers described above, or serve as a medium for forming polymer
suspensions as part of inks. The solvents may be selected to
improve rheology of the inks. The remnants of some solvents in
dried layers can improve the electrical performance of the
supercapacitor.
To achieve these and/or other advantages, solvents can include one
or more of water and alcohols such as methanol, ethanol, N-propanol
(including 1-propanol, 2-propanol (isopropanol or IPA),
1-methoxy-2-propanol), butanol (including 1-butanol, 2-butanol
(isobutanol)), pentanol (including 1-pentanol, 2-pentanol,
3-pentanol), hexanol (including 1-hexanol, 2-hexanol, 3-hexanol),
octanol, N-octanol (including 1-octanol, 2-octanol, 3-octanol),
tetrahydrofurfuryl alcohol (THFA), cyclohexanol, cyclopentanol,
terpineol; lactones such as butyl lactone; ethers such as methyl
ethyl ether, diethyl ether, ethyl propyl ether, and polyethers;
ketones, including diketones and cyclic ketones, such as
cyclohexanone, cyclopentanone, cycloheptanone, cyclooctanone,
acetone, benzophenone, acetylacetone, acetophenone, cyclopropanone,
isophorone, methyl ethyl ketone; esters such ethyl acetate,
dimethyl adipate, propylene glycol monomethyl ether acetate,
dimethyl glutarate, dimethyl succinate, glycerin acetate,
carboxylates; carbonates such as propylene carbonate; polyols (or
liquid polyols), glycerols and other polymeric polyols or glycols
such as glycerin, diol, triol, tetraol, pentanol, ethylene glycols,
diethylene glycols, polyethylene glycols, propylene glycols,
dipropylene glycols, glycol ethers, glycol ether acetates
1,4-butanediol, 1,2-butanediol, 2,3-butanediol, 1,3-propanediol,
1,4-butanediol, 1,5-pentanediol, 1,8-octanediol, 1,2-propanediol,
1,3-butanediol, 1,2-pentanediol, etohexadiol, p-menthane-3,8-diol,
2-methyl-2,4-pentanediol; tetramethyl urea, n-methylpyrrolidone,
acetonitrile, tetrahydrofuran (THF), dimethyl formamide (DMF),
N-methyl formamide (NMF), dimethyl sulfoxide (DMSO); thionyl
chloride; sulfuryl chloride; dibasic ester, diethylene glycol
monoethyl ether acetate, combinations thereof, and the like.
Organic solvents can include one or more of acetonitrile, propylene
carbonate, ethylene carbonate, diethyl carbonate, dimethyl
carbonate, ethyl acetate, 1,1,1,3,3,3-hexafluoropropan-2-ol,
adiponitrile, 1,3-propylene sulfite, butylene carbonate,
.UPSILON.-Butyrolactone, .UPSILON.-Valerolactone, propionitrile,
glutaronitrile, adiponitrile, methoxyacetonitrile,
3-methoxypropionitrile, N,N-Dimethylformamide,
N,N-Dimethylacetamide, N-Methylpyrrolidinone,
N-Methyloxazolidinone, N,N''-Dimethylimidazolininone, nitromethane,
nitroethane, sulfonate, 3-Methylsulfonate, dimethylsulfoxide,
trimethyl phosphate, combinations thereof, and the like.
Electrolytes according to some embodiments include ionic liquids
(ILs). As described herein, IL refers to a salt in the liquid state
at operation temperatures of the supercapacitors. For example,
without limitation, IL can be in the liquid molten form at
temperature below 100.degree. C. Some ILs can consist essentially
of ions, including a cation and an anion. The ILs can include
combinations of the following example cations and anions.
Examples of cations that can be included in the ILs for
supercapacitors include butyltrimethylammonium,
1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium,
1-methyl-3-propylimidazolium, 1-hexyl-3-methylimidazolium, choline,
ethylammonium, tributylmethylphosphonium,
tributyl(tetradecyl)phosphonium, trihexyl(tetradecyl)phosphonium,
1-ethyl-2,3-methylimidazolium, 1-butyl-1-methylpiperidinium,
diethylmethylsulfonium, 1-methyl-3-propylimidazolium,
1-ethyl-3-methylimidazolium, 1-methyl-1-propylpiperidinium,
1-butyl-2-methylpyridinium, 1-butyl-4-methylpyridinium,
1-butyl-1-methylpyrrolidinium, diethylmethylsulfonium, combinations
thereof, and the like.
Examples of anions that can be included in the ILs for
supercapacitors include tris(pentafluoroethyl)trifluorophosphate,
trifluoromethanesulfonate, hexafluorophosphate, tetrafluoroborate,
ethyl sulfate, dimethyl phosphate, methansulfonate, triflate,
tricyanomethanide, dibutylphosphate,
bis(trifluoromethylsulfonyl)imide, bis-2,4,4-(trimethylpentyl)
phosphinate, iodide, chloride, bromide, nitrate, combinations
thereof, and the like.
According to some embodiments, the electrolyte or the IL of the
supercapacitors additionally includes one or more salts dissolved
in the electrolyte or dissolved in the IL when present. Salts in
the electrolytes include combinations of a cation and an anion.
The cation of the salt can be selected from one or more of zinc,
sodium, potassium, magnesium, calcium, aluminum, lithium, barium,
combinations thereof, and the like.
The anion of the salt can be selected from one or more of chloride,
bromide, fluoride, bis(trifluoromethanesulfonyl)imide, sulfate,
bisulfite, nitrate, nitrite, carbonate, hydroxide, perchloride,
bicarbonate, tetrafluoroborate, methansulfonate, acetate,
phosphate, citrate, hexafluorophosphate, combinations thereof, and
the like.
The electrolyte can include an organic salt, an inorganic salt, an
acid, or a base.
Examples of organic salts include tetraethylammonium
tetrafluoroborate, tetraethylammonium difluoro(oxalate)borate,
methylammonium tetrafluoroborate, triethylmethylammonium
tetrafluoroborate, tetrafluoroboric acid dimethyldi ethylammonium,
triethylmethylammonium tetrafluoroborate, tetrapropylammonium
tetrafluoroborate, methyltributylammonium tetrafluoroborate,
tetrabutylammonium tetrafluoroborate, tetrahexylammonium
tetrafluoroborate, tetramethylammonium tetrafluoroborate,
tetraethyl phosphonium tetrafluoroborate, tetrapropylphosphonium
tetrafluoroborate, tetrabutylphosphonium, tetrafluoroborate,
combinations thereof, and the like.
Examples of acid include H.sub.2SO.sub.4, HCl, HNO.sub.3,
HClO.sub.4, combinations thereof, and the like.
Examples of base include KOH, NaOH, LiOH, NH.sub.4OH, combinations
thereof, and the like.
Examples of inorganic salts include LiCl, Li.sub.2SO.sub.4,
LiClO.sub.4, NaCl, Na.sub.2SO.sub.4, NaNO.sub.3, KCl,
K.sub.2SO.sub.4, KNO.sub.3, Ca(NO.sub.3).sub.2, MgSO.sub.4,
combinations thereof, and the like.
Any other salts, electrolytes or ionic liquids disclosed herein are
possible.
Ionic liquids can serve as the electrolyte and/or be included as
part of the electrolyte, with or without salts. Ionic liquids can
be used with non-aqueous electrolytes and/or with water.
According to various embodiments, particular electrolytes can be
selected to form gel electrolytes by mixing with polymers or other
matrices.
Supercapacitor Configurations
The geometric arrangement of electrodes and the separator of
supercapacitors according to various embodiments can have any one
of the configurations illustrated on FIG. 7. In some embodiments,
the electrodes of the supercapacitor can be arranged symmetrically
or asymmetrically. As described herein, when electrodes having
opposing polarities (e.g., cathode and an anode or a positive
electrode and a negative electrode) are configured symmetrically,
both types of electrodes are configured to store charge
predominantly as EDLCs or predominantly as pseudo capacitors.
As described herein, an electrode that is configured to store
charge predominantly through one of the two types of storage
mechanisms exhibits a capacitance value that arises predominantly
from the type of storage mechanisms over the other. For example,
when an electrode is configured to store energy predominantly
through one of the electric double layer capacitance or pseudo
capacitance mechanisms, at least 80%, 90%, 95%, 99%, or a value in
a range defined by any of these values, of the net capacitance
value may arise from the one of the electric double layer
capacitance or pseudo capacitance mechanisms. For example, when the
surface active material comprises one but not the other of (1) CNT
or (2) manganese oxide and/or zinc oxide, the electrode may be
predominantly configured as one but not the other of an EDLC or a
pseudo capacitor. And when the surface active material comprises
both (1) CNT and (2) manganese oxide and/or zinc oxide, the
electrode may be predominantly configured as an EDLC when the
relative amount of manganese oxide and/or zinc oxide is low
compared to the relative amount of CNT, and vice versa.
When an electrode is configured to store energy substantially
through both of the electric double layer capacitance and pseudo
capacitance mechanisms, 20-80%, 30-70%, 40-60%, or a value in a
range defined by any of these values, of the net capacitance value
may arise from the one of the electric double layer capacitance or
pseudo capacitance mechanisms, while the balance may substantially
be attributable to the other of the electric double layer
capacitance or pseudo capacitance mechanisms. For example, when the
surface active material comprises both (1) CNT and (2) manganese
oxide and/or zinc oxide, the electrode may be substantially
configured as an EDLC as well as a pseudo capacitor when the
relative amounts of both (1) CNT and (2) manganese oxide and/or
zinc oxide are substantial or effective to give rise to the above
percentage values of capacitance values attributable to each of the
mechanisms.
When electrodes having opposing types polarities (e.g., cathode and
an anode or a positive electrode and a negative electrode) are
configured asymmetrically, one of the two types of electrodes is
configured to store charge predominantly as one of a an EDLC or a
pseudo capacitor, while the other one of the two types of
electrodes is configured to store charge predominantly as the other
of the EDLC or a pseudo capacitor.
When the electrodes of opposite charge types are configured
symmetrically, the electrodes of both types of charge may include
frustules having nanostructures of the same type. For example,
electrodes of both types may include zinc-oxide, e.g., frustules
having formed thereon zinc oxide (Zn.sub.xO.sub.y, e.g., ZnO)
nanostructures, manganese-oxide, e.g., frustules having formed
thereon manganese oxide (MnO.sub.xO.sub.y) nanostructures, and/or
carbon, e.g., frustules having formed thereon carbon
nanostructures, e.g., carbon nanotube (CNTs). When the electrodes
of opposite charge types are configured asymmetrically, the
electrodes of different types of charge may include frustules
having different ones of these nanostructures. Symmetric
supercapacitors having electrodes of both charge types that include
the same metal oxide on frustules, e.g., Zn.sub.xO.sub.y or
Mn.sub.xO.sub.y are predominantly pseudo capacitors. Symmetric
supercapacitors having electrodes of both charge types that include
carbon nanostructures on frustules, e.g., CNT, are predominantly
EDLCs. Asymmetric supercapacitors having an electrode of first
charge type that includes one of transition metal oxides and an
electrode of second charge type that includes CNT on frustules
without transition metal oxides, e.g., first and second surface
active materials that include Mn.sub.xO.sub.y and CNT,
respectively, and Zn.sub.xO.sub.y and CNT, respectively, are hybrid
capacitors that combine characteristics of both a pseudo capacitor
on one electrode and an EDLC on the other electrode.
Supercapacitors can comprise a suitable commercially available
separator or a printed separator, e.g., a printed separator
comprising frustules and/or graphene oxide.
In some embodiments, supercapacitors comprise an ionic liquid that
serves as an electrolyte. In some embodiments, supercapacitors
comprise a combination of an ionic liquid and one of both of a salt
and a solvent serving as an electrolyte. In some embodiments, the
electrolyte essentially consists of an ionic liquid.
A current collector can comprise a suitable electrically conducting
material, e.g. Al, Cu, Ni, stainless steel, graphite/graphene/CNTs,
foil, etc. The foils can be laminated with a polymer from one side.
A current collector can be formed from a printed conductive ink.
The ink can include Al, Ni, Ag, Cu, Bi, carbon, carbon nanotubes,
graphene, graphite and other conductive metals and mixture of
thereof.
Substrates on which different layers are printed can be conductive
or non-conductive. Advantageously, the various layers of the
supercapacitors disclosed herein can be printed on flexible
substrates having flexibility comparable to, e.g., a cloth. The
substrates can include graphite paper, graphene paper, polyester
film, polyimide film, Al foil, Cu foil, stainless foil, carbon
foam, polycarbonate film, paper, coated paper, plastic coated
paper, fiber paper and/or cardboard, to name a few.
After printing the various layers, supercapacitors can be
encapsulated by lamination, e.g., by printing/depositing a
protective layer, for example.
The supercapacitors can be printed in any suitable shape.
Supercapacitors can be printed such that they are electrically
connected in in parallel and/or electrically connected in series.
Supercapacitors can be printed such that they are electrically
connected in parallel and/or series with printed batteries.
Advantageously, the overall thickness of supercapacitor can be made
extremely thin. The entire supercapacitor, including the substrate,
can have a thickness of 10-50 microns, 50-100 microns, 100-200
microns, 200-300 microns, 300-400 microns, 400-500 microns, 500-600
microns, 600-700 microns, 700-800 microns 800-900 microns, 900-1000
microns, 1000-1200 microns, 1200-1400 microns, 1400-1600 microns,
1600-1800 microns, 1800-2000 microns, or a thickness in a range
defined by any of these values.
Supercapacitor Fabrication Method
Advantageously, using the inks described above, one or more or all
layers of the supercapacitor can be printed. The one or more layers
or the entire supercapacitor can be printed using any of the
printing techniques described herein. Example printing processes
that can be used to print the one or more layers include coating,
rolling, spraying, layering, spin coating, lamination and/or
affixing processes, for example, screen printing, inkjet printing,
electro-optical printing, electroink printing, photoresist and
other resist printing, thermal printing, laser jet printing,
magnetic printing, pad printing, flexographic printing, hybrid
offset lithography, gravure and other intaglio printing, die slot
deposition, among other suitable printing techniques.
The inks for printing one or more layers of the supercapacitor can
be prepared by mixing various ink components described above, using
any of the ink mixing techniques described herein, including mixing
with a stir bar, mixing with a magnetic stirrer, vortexing (using a
vortex machine), shaking (using a shaker), planetary centrifugal
mixing, by rotation, three roll milling, ball milling, sonication
and mixing using mortar and pestle, to name a few.
One or more layers printed using inks described above, including
the electrodes and/or the separator, can be treated using various
processes described above, including drying/curing techniques
including short wave infrared (IR) radiation, medium wave
IR-radiation, hot air conventional ovens, electron beam curing and
near infrared radiation, among other techniques. When cured using
convectional and IR ovens, the layers are subjected to a
temperature range of 50-200.degree. C., 75-175.degree. C.,
100-150.degree. C. or any temperature in a range defined by any of
these values, for a duration of 1 to 60 minutes, 2 to 40 minutes,
3-15 minutes, or any duration in a range defined by any of these
values.
The one or more layers printed using inks described above,
including the electrodes and/or the separators, can be cured/dried
using near-infrared (NIR) light energy, using a suitable equipment
configured to generate such light source. One example equipment
that can be used is available from Adphos Group. Using NIR light
energy to dry/cure the printed layers can advantageously include
shorter drying times, e.g., by as much as an order of magnitude
shorter (e.g., in seconds rather than minutes) than drying times
employed using IR or conventional ovens. The inventors have
discovered that the NIR radiation penetrates deeper into the
printed layers printed more effectively and quickly, thereby
removing solvents from the entire thickness of the printed layers
more effectively and quickly. To facilitate even faster drying of
the printed layers, when NIR radiation is used, heat-absorbing
particles can be included in the ink for the printed layers,
thereby further improving the efficiency of the drying process. In
some printed layers, such as electrodes, surface active materials
such as CNTs, Mn.sub.xO.sub.y or Zn.sub.xO.sub.y as well as other
electrically conductive carbon included in the printed electrode
layers can serve as heat-absorbing particles to facilitate drying
of the printed layers. In some printed layers, such as separators,
thermally conductive additives, graphene oxide (GO), may be added
to serve as heat-absorbing particles to facilitate drying of the
printed layers. As described herein, because the thermally
conductive additive such as GO can be a good electrical insulator,
the separator advantageously maintains the electrically insulating
characteristics, while serving as a heat absorbing material. The
inventors have found, when included as part of a printed layer such
as a printed separator layer, GO may reduce the drying time by as
much as one order of magnitude, e.g., from tens or minutes to tens
of seconds. When NIR radiation is used, the layers can be
dried/cured for a duration of 1-60 sec., 1-45 sec., 1-30 sec. or
for a duration in a range defined by any of these values, which is
significantly shorter than drying/curing times that maybe employed
using other light sources, e.g., IR light sources.
Experimental Performance of Supercapacitors
FIGS. 16A and 16B illustrate experimental measurements performed on
a supercapacitor having symmetric printed electrodes, where each of
the electrodes having opposite polarities comprises frustules
having formed thereon zinc oxide (Zn.sub.xO.sub.y, e.g., ZnO)
nanostructures, such that the supercapacitor is configured as a
pseudo capacitor. FIG. 16A illustrates a charge/discharge curve
measured on a supercapacitor having square electrodes (1.6
cm.times.1.6 cm). The capacitor was charged/discharged at 1 mA, and
the charge time was 500 sec. The measured capacitance was about
0.06 F. The cut-off voltage for calculations was 1V. FIG. 16B
illustrates a charge/discharge curve measured on a similar
capacitor as that illustrated in FIG. 16A, in which the
supercapacitor was charged/discharged at a higher current 10 mA.
The cut-off voltage for charging was 3V. The measured capacitance
was about 0.04 F. The cut-off voltage for calculations was 1V.
FIGS. 17A-17D illustrate experimental measurements performed on a
supercapacitor having symmetric printed electrodes, where each of
the electrodes having opposite polarities comprises frustules
having formed thereon manganese oxide (Mn.sub.xO.sub.y)
nanostructures, such that the supercapacitor is configured as a
pseudo capacitor. FIG. 17A illustrates a charge/discharge curve
measured on a supercapacitor having square electrodes (1.6
cm.times.1.6 cm). The capacitor was charged/discharged at 2 mA, and
the charge time was 500 sec. The measured capacitance was about
0.14 F. The cut-off voltage for calculations was 1V.
FIG. 17B illustrates a charge/discharge curve measured on a
supercapacitor having square electrodes (1.6 cm.times.1.6 cm). The
capacitor was charged at 40 mA for 3 sec. and discharged at 0.4 mA.
The measured average capacitance was about 0.06 F. The cut-off
voltage for calculations was 1V. The capacitance value was observed
to increase with cycling. While only a few cycles are shown, the
capacitor was successfully cycled 1000 times without degradation.
As illustrated, the capacitors were demonstrated to charge
relatively quickly, which is an advantageous property of
supercapacitors over batteries, as described above.
FIG. 17C illustrates a discharge curve measured on a supercapacitor
having square electrodes (1.6 cm.times.1.6 cm). The capacitor was
charged at 40 mA for 3 sec. and discharged at 0.4 mA. The measured
average capacitance was about 0.055 F. The cut-off voltage for
calculations was 1V. While only one cycle (330.sup.th cycle) is
shown for illustrative purposes, the capacitor was successfully
cycled more than 1000 times without substantial deterioration.
FIG. 17D illustrates a discharge curve measured on a supercapacitor
having square electrodes (1.6 cm.times.1.6 cm). The capacitor was
charged at 40 mA for 3 sec. and discharged at 0.4 mA. The measured
average capacitance was about 0.061 F. The cut-off voltage for
calculations was 1V. While only one cycle (1000.sup.th cycle) is
shown for illustrative purposes, the capacitor was successfully
cycled more than 1000 times without substantial deterioration.
FIGS. 18A-18E illustrate experimental measurements performed on a
supercapacitor having asymmetric printed electrodes, where one of
the electrodes having opposite polarities comprises frustules
having formed thereon manganese oxide (Mn.sub.xO.sub.y)
nanostructures, while the other of the electrodes comprises
frustules having formed thereon CNT, such that the supercapacitor
is configured as a hybrid supercapacitor. The specific capacitance
(C.sub.sp), which can be defined as the measured capacitance
multiplied by the specific surface area, of 100-340 F/g at specific
current of 0.01-1 A/g was obtained based on the amount of surface
active material.
FIG. 18A illustrates a discharge curve measured on a supercapacitor
having square electrodes (2.54. cm.times.2.54 cm). The capacitor
was charged at a constant voltage of 2V for 30 minutes and
discharged at 2 mA. The measured capacitance was about 2.21 F. The
cut-off voltage for calculations was 1V.
FIG. 18B illustrates a discharge curve measured on a supercapacitor
having square electrodes (2.54. cm.times.2.54 cm). The capacitor
was charged at a constant voltage of 2V for 30 minutes and
discharged at 2 mA. The measured capacitance was about 3.26 F. The
cut-off voltage for calculations was 1V.
FIG. 18C illustrates a discharge curve measured on a supercapacitor
having square electrodes (2.54. cm.times.2.54 cm). The capacitor
was charged at constant voltage of 3V for 30 minutes and discharged
at 2 mA. The measured capacitance was about 3.86 F. The cut-off
voltage for calculations was 1V.
FIG. 18D illustrates a charge/discharge curve measured on a
supercapacitor having square electrodes (2.54. cm.times.2.54 cm).
The capacitor was charged at 0.1 A for 2 sec. and discharged at 1
mA. The measured capacitance was about 1.36 F. The cut-off voltage
for calculations was 1V. As illustrated, the capacitor charged
relatively quickly, which is an advantageous property of
supercapacitors over batteries, as described above.
FIG. 18E illustrates a charge/discharge curve measured on a
supercapacitor having square electrodes (2.54. cm.times.2.54 cm).
The capacitor was charged to 4.5V at 2 mA for 2 sec. and discharged
at 1 mA. The cut-off voltage for calculations was 2V. As
illustrated, the capacitors charged relatively quickly, which is an
advantageous property of supercapacitors over batteries, as
described above.
FIGS. 19A-19B illustrate experimental measurements performed on a
supercapacitor having symmetric printed electrodes, where each of
the electrodes having opposite polarities comprises frustules
having formed thereon CNT, such that the supercapacitor is
configured as a double layer supercapacitor. The specific
capacitance (C.sub.sp) was 50-100 F/g at specific current of 0.01-1
A/g based on the amount of surface active material.
FIG. 19A illustrates a charge/discharge curve measured on a
supercapacitor having square electrodes (1.6 cm.times.1.6 cm). The
capacitor was charged at 1 mA for 500 sec. and discharged at 1 mA.
The measured capacitance was about 0.08 F. The cut-off voltage for
calculations was 1V.
FIG. 19B illustrates a discharge curve measured on a supercapacitor
having square electrodes (2.54. cm.times.2.54 cm). The capacitor
was charged to 3V at 5 mA and discharged at 5 mA. The measured
capacitance was about 0.06 F. The cut-off voltage for calculations
was 1V.
EXAMPLE EMBODIMENTS
The following example embodiments identify some possible
permutations of combinations of features disclosed herein, although
other permutations of combinations of features are also
possible.
1. A printed energy storage device comprising: a first electrode; a
second electrode; and a separator between the first electrode and
the second electrode, at least one of the first electrode, the
second electrode, and the separator including frustules.
2. The device of Embodiment 1, wherein the separator includes the
frustules.
3. The device of Embodiment 1 or 2, wherein the first electrode
includes the frustules.
4. The device of any of Embodiments 1-3, wherein the second
electrode includes the frustules.
5. The device of any one of Embodiments 1-4, wherein the frustules
have a substantially uniform property.
6. The device of Embodiment 5, wherein property comprises
shape.
7. The device of Embodiment 6, wherein the shape comprises a
cylinder, a sphere, a disc, or a prism.
8. The device of any of Embodiments 5-7, wherein the property
comprises a dimension.
9. The device of Embodiment 8, wherein the dimension comprises
diameter.
10. The device of Embodiment 9, wherein the diameter is in a range
from about 2 .mu.m to about 10 .mu.m.
11. The device of Embodiment 8, wherein the dimension comprises
length.
12. The device of Embodiment 9, wherein the length is in a range
from about 5 .mu.m to about 20 .mu.m.
13. The device of Embodiment 8, wherein the dimension comprises a
longest axis.
14. The device of Embodiment 9, wherein the longest axis is in a
range from about 5 .mu.m to about 20 .mu.m.
15. The device of any of Embodiments 5-14, wherein the property
comprises porosity.
16. The device of Embodiment 15, wherein the porosity is in a range
from about 20% to about 50%.
17. The device of any of Embodiments 5-16, wherein the property
comprises mechanical strength.
18. The device of any of Embodiment 1-17, wherein the frustules
comprise a surface modifying structure.
19. The device of Embodiment 18, wherein the surface modifying
structure includes a conductive material.
20. The device of Embodiment 19, wherein the conductive material
includes at least one of silver, aluminum, tantalum, copper,
lithium, magnesium, and brass.
21. The device of any of Embodiments 18-20, wherein the surface
modifying structure includes zinc oxide (ZnO).
22. The device of any of Embodiments 18-21, wherein the surface
modifying structure includes a semiconductor.
23. The device of Embodiment 22, wherein the semiconductor includes
at least one of silicon, germanium, silicon germanium, and gallium
arsenide.
24. The device of any of Embodiments 18-23, wherein the surface
modifying structure comprises at least one of a nanowire, a
nanoparticle, and a structure having a rosette shape.
25. The device of any of Embodiments 18-24, wherein the surface
modifying structure is on an exterior surface of the frustules.
26. The device of any of Embodiments 18-25, wherein the surface
modifying structure is on an interior surface of the frustules.
27. The device of any of Embodiments 1-26, wherein the frustules
comprise a surface modifying material.
28. The device of Embodiment 27, wherein the surface modifying
material includes a conductive material.
29. The device of Embodiment 28, wherein the conductive material
includes at least one of silver, aluminum, tantalum, copper,
lithium, magnesium, and brass.
30. The device of any of Embodiments 27-29, wherein the surface
modifying material includes zinc oxide (ZnO).
31. The device of any of Embodiments 27-30, wherein the surface
modifying material includes a semiconductor.
32. The device of Embodiment 31, wherein the semiconductor includes
at least one of silicon, germanium, silicon germanium, and gallium
arsenide.
33. The device of any of Embodiments 27-32, wherein the surface
modifying material is on an exterior surface of the frustules.
34. The device of any of Embodiments 37-33, wherein the surface
modifying material is on an interior surface of the frustules.
35. The device of any of Embodiments 1-34, wherein the first
electrode comprises a conductive filler.
36. The device of any of Embodiments 1-35, wherein the second
electrode comprises a conductive filler.
37. The device of Embodiment 34 or 35, wherein the conductive
filler comprises graphitic carbon.
38. The device of any of Embodiments 35-37, wherein the conductive
filler comprises graphene.
39. The device of any of Embodiments 1-38, wherein the first
electrode comprises an adherence material.
40. The device of any of Embodiments 1-39, wherein the second
electrode comprises an adherence material.
41. The device of any of Embodiments 1-40, wherein the separator
comprises an adherence material.
42. The device of any of Embodiments 39-41, wherein the adherence
material comprises a polymer.
43. The device of any of Embodiments 1-42, wherein the separator
comprises an electrolyte.
44. The device of Embodiment 43, wherein the electrolyte comprises
at least one of an ionic liquid, an acid, a base, and a salt.
45. The device of Embodiment 43 or 44, wherein the electrolyte
comprises an electrolytic gel.
46. The device of any of Embodiments 1-45, further comprising a
first current collector in electrical communication with the first
electrode.
47. The device of any of Embodiments 1-46, further comprising a
second current collector in electrical communication with the
second electrode.
48. The device of any of Embodiments 1-47, wherein the printed
energy storage device comprises a capacitor.
49. The device of any of Embodiments 1-47, wherein the printed
energy storage device comprises a supercapacitor.
50. The device of any of Embodiments 1-47, wherein the printed
energy storage device comprises a battery.
51. A system comprising a plurality of the devices of any of
Embodiments 1-50 stacked on top of each other.
52. An electrical device comprising the device of any of
Embodiments 1-50 or the system of Embodiment 51.
53. A membrane for a printed energy storage device, the membrane
comprising frustules.
54. The membrane of Embodiment 53, wherein the frustules have a
substantially uniform property.
55. The membrane of Embodiment 54, wherein the property comprises
shape.
56. The membrane of Embodiment 55, wherein the shape comprises a
cylinder, a sphere, a disc, or a prism.
57. The membrane of any of Embodiments 54-56, wherein the property
comprises a dimension.
58. The membrane of Embodiment 57, wherein the dimension comprises
diameter.
59. The membrane of Embodiment 58, wherein the diameter is in a
range from about 2 .mu.m to about 10 .mu.m.
60. The membrane of any of Embodiments 54-59, wherein the dimension
comprises length.
61. The membrane of Embodiment 60, wherein the length is in a range
of about 5 to about 20 .mu.m.
62. The membrane of any of Embodiments 54-61, wherein the dimension
comprises a longest axis.
63. The membrane of Embodiment 62, wherein the longest axis is in a
range of about 5 .mu.m to about 20 .mu.m.
64. The membrane of any of Embodiments 54-63, wherein the property
comprises porosity.
65. The membrane of Embodiment 64, wherein the porosity is in a
range from about 20% to about 50%.
66. The membrane of any of Embodiments 54-65, wherein the property
comprises mechanical strength.
67. The membrane of any of Embodiments 53-66, wherein the frustules
comprise a surface modifying structure.
68. The membrane of Embodiment 67, wherein the surface modifying
structure includes a conductive material.
69. The membrane of Embodiment 68, wherein the conductive material
includes at least one of silver, aluminum, tantalum, copper,
lithium, magnesium, and brass.
70. The membrane of any of Embodiments 67-69, wherein the surface
modifying structure includes zinc oxide (ZnO).
71. The membrane of any of Embodiments 67-70, wherein the surface
modifying structure includes a semiconductor.
72. The membrane of Embodiment 71, wherein the semiconductor
includes at least one of silicon, germanium, silicon germanium, and
gallium arsenide.
73. The membrane of any of Embodiments 67-72, wherein the surface
modifying structure comprises at least one of a nanowire, a
nanoparticle, and a structure having a rosette shape.
74. The membrane of any of Embodiments 67-73, wherein the surface
modifying structure is on an exterior surface of the frustules.
75. The membrane of any of Embodiments 67-74, wherein the surface
modifying structure is on an interior surface of the frustules.
76. The membrane of any of Embodiments 53-75, wherein the frustules
comprises a surface modifying material.
77. The membrane of Embodiment 76, wherein surface modifying
material includes a conductive material.
78. The membrane of Embodiment 77, wherein the conductive material
includes at least one of silver, aluminum, tantalum, copper,
lithium, magnesium, and brass.
79. The membrane of any of Embodiments 76-78, wherein the surface
modifying material includes zinc oxide (ZnO).
80. The membrane of any of Embodiments 76-79, wherein the surface
modifying material includes a semiconductor.
81. The membrane of Embodiment 80, wherein the semiconductor
includes at least one of silicon, germanium, silicon germanium, and
gallium arsenide.
82. The membrane of any of Embodiments 76-81, wherein the surface
modifying material is on an exterior surface of the frustules.
83. The membrane of any of Embodiments 76-82, wherein the surface
modifying material is on an interior surface of the frustules.
84. The membrane of any of Embodiments 83-83, further comprising a
conductive filler.
85. The membrane of Embodiment 84, wherein the conductive filler
comprises graphitic carbon.
86. The membrane of Embodiment 84 or 85, wherein the conductive
filler comprises graphene.
87. The membrane of any of Embodiments 53-86, further comprising an
adherence material.
88. The membrane of Embodiment 87, wherein the adherence material
comprises a polymer.
89. The membrane of any of Embodiments 53-88, further comprising an
electrolyte.
90. The membrane of Embodiment 89, wherein the electrolyte
comprises at least one of an ionic liquid, an acid, a base, and a
salt.
91. The membrane of Embodiment 89 or 90, wherein the electrolyte
comprises an electrolytic gel.
92. An energy storage device comprising the membrane of any of
Embodiments 53-91.
93. The device of Embodiment 92, wherein the printed energy storage
device comprises a capacitor.
94. The device of Embodiment 92, wherein the printed energy storage
device comprises a supercapacitor.
95. The device of Embodiment 92, wherein the printed energy storage
device comprises a battery.
96. A system comprising a plurality of the devices of any of
Embodiments 92-95 stacked on top of each other.
97. An electrical device comprising the device of any of
Embodiments 92-95 or the system of Embodiment 96.
98. A method of manufacturing a printed energy storage device, the
method comprising: forming a first electrode; forming a second
electrode; and forming a separator between the first electrode and
the second electrode, at least one of the first electrode, the
second electrode, and the separator including frustules.
99. The method of Embodiment 98, wherein the separator includes the
frustules.
100. The method of Embodiment 99, wherein forming the separator
includes forming a dispersion including the frustules.
101. The method of Embodiment 99 or 100, wherein forming the
separator includes screen printing the separator.
102. The method of Embodiment 99, wherein forming the separator
includes forming a membrane including the frustules.
103. The method of Embodiment 102, wherein forming the separator
includes roll-to-roll printing the membrane including the
separator.
104. The method of any of Embodiments 98-103, wherein the first
electrode includes the frustules.
105. The method of Embodiment 104, wherein forming the first
electrode includes forming a dispersion including the
frustules.
106. The method of Embodiment 104 or 105, wherein forming the first
electrode includes screen printing the first electrode.
107. The method of Embodiment 104, wherein forming the first
electrode includes forming a membrane including the frustules.
108. The method of Embodiment 107, wherein forming the first
electrode includes roll-to-roll printing the membrane including the
first electrode.
109. The method of any of Embodiments 98-108, wherein the second
electrode includes the frustules.
110. The method of Embodiment 109, wherein forming the second
electrode includes forming a dispersion including the
frustules.
111. The method of Embodiment 109 or 110, wherein forming the
second electrode includes screen printing the second electrode.
112. The method of Embodiment 109, wherein forming the second
electrode includes forming a membrane including the frustules.
113. The method of Embodiment 112, wherein forming the second
electrode includes roll-to-roll printing the membrane including the
second electrode.
114. The method of any of Embodiments 98-113, further comprising
sorting the frustules according to a property.
115. The method of Embodiment 114, wherein the property comprises
at least one of shape, dimension, material, and porosity.
116. An ink comprising: a solution; and frustules dispersed in the
solution.
117. The ink of Embodiment 116, wherein the frustules have a
substantially uniform property.
118. The ink of Embodiment 117, wherein the property comprises
shape.
119. The ink of Embodiment 118, wherein the shape comprises a
cylinder, a sphere, a disc, or a prism.
120. The ink of any of Embodiments 117-119, wherein the property
comprises a dimension.
121. The ink of Embodiment 120, wherein the dimension comprises
diameter.
122. The ink of Embodiment 121, wherein the diameter is in a range
from about 2 .mu.m to about 10 .mu.m.
123. The ink of any of Embodiments 117-122, wherein the dimension
comprises length.
124. The ink of Embodiment 123, wherein the length is in a range of
about 5 .mu.m to about 20 .mu.m.
125. The ink of any of Embodiments 117-124, wherein the dimension
comprises a longest axis.
126. The ink of Embodiment 125, wherein the longest axis is in a
range of about 5 to about 20 .mu.m.
127. The ink of any of Embodiments 117-126, wherein the property
comprises porosity.
128. The ink of Embodiment 127, wherein the porosity is in a range
from about 20% to about 50%.
129. The ink of any of Embodiments 117-128, wherein the property
comprises mechanical strength.
130. The ink of any of Embodiments 116-129, wherein the frustules
comprise a surface modifying structure.
131. The ink of Embodiment 130, wherein the surface modifying
structure includes a conductive material.
132. The ink of Embodiment 131, wherein the conductive material
includes at least one of silver, aluminum, tantalum, copper,
lithium, magnesium, and brass.
133. The ink of any of Embodiments 130-132, wherein the surface
modifying structure includes zinc oxide (ZnO).
134. The ink of any of Embodiments 130-133, wherein the surface
modifying structure includes a semiconductor.
135. The ink of Embodiment 134, wherein the semiconductor includes
at least one of silicon, germanium, silicon germanium, and gallium
arsenide.
136. The ink of any of Embodiments 130-135, wherein the surface
modifying structure comprises at least one of a nanowire, a
nanoparticle, and a structure having a rosette shape.
137. The ink of any of Embodiments 130-136, wherein the surface
modifying structure is on an exterior surface of the frustules.
138. The ink of any of Embodiments 130-137, wherein the surface
modifying structure is on an interior surface of the frustules.
139. The ink of any of Embodiments 116-138, wherein the frustules
comprises a surface modifying material.
140. The ink of Embodiment 139, wherein surface modifying material
includes a conductive material.
141. The ink of Embodiment 140, wherein the conductive material
includes at least one of silver, aluminum, tantalum, copper,
lithium, magnesium, and brass.
142. The ink of any of Embodiments 139-141, wherein the surface
modifying material includes zinc oxide (ZnO).
143. The ink of any of Embodiments 139-142, wherein the surface
modifying material includes a semiconductor.
144. The ink of Embodiment 143, wherein the semiconductor includes
at least one of silicon, germanium, silicon germanium, and gallium
arsenide.
145. The ink of any of Embodiments 139-144, wherein the surface
modifying material is on an exterior surface of the frustules.
146. The ink of any of Embodiments 139-145, wherein the surface
modifying material is on an interior surface of the frustules.
147. The ink of any of Embodiments 116-146, further comprising a
conductive filler.
148. The ink of Embodiment 147, wherein the conductive filler
comprises graphitic carbon.
149. The ink of Embodiment 147 or 148, wherein the conductive
filler comprises graphene.
150. The ink of any of Embodiments 116-149, further comprising an
adherence material.
151. The ink of Embodiment 150, wherein the adherence material
comprises a polymer.
152. The ink of any of Embodiments 116-151, further comprising an
electrolyte.
153. The ink of Embodiment 152, wherein the electrolyte comprises
at least one of an ionic liquid, an acid, a base, and a salt.
154. The ink of Embodiment 152 or 153, wherein the electrolyte
comprises an electrolytic gel.
155. A device comprising the ink of any of Embodiments 116-154.
156. The device of Embodiment 155, wherein the device comprises a
printed energy storage device.
157. The device of Embodiment 156, wherein the printed energy
storage device comprises a capacitor.
158. The device of Embodiment 156, wherein the printed energy
storage device comprises a supercapacitor.
159. The device of Embodiment 156, wherein the printed energy
storage device comprises a battery.
160. A method of extracting a diatom frustule portion, the method
comprising: dispersing a plurality of diatom frustule portions in a
dispersing solvent; removing at least one of an organic contaminant
and an inorganic contaminant; dispersing the plurality of diatom
frustule portions in a surfactant, the surfactant reducing an
agglomeration of the plurality of diatom frustule portions; and
extracting a plurality of diatom frustule portions having at least
one common characteristic using a disc stack centrifuge.
161. The method of embodiment 160, wherein the at least one common
characteristic comprises at least one of a dimension, a shape, a
material, and a degree of brokenness.
162. The method of embodiment 161, wherein the dimension comprises
at least one of a length and a diameter.
163. The method of any one of embodiments 160 to 162, wherein a
solid mixture comprises the plurality of diatom frustule
portions.
164. The method of embodiment 163, further comprising reducing a
particle dimension of the solid mixture.
165. The method of embodiment 164, wherein reducing the particle
dimension of the solid mixture is before dispersing the plurality
of diatom frustule portions in the dispersing solvent.
166. The method of embodiment 164 or 165, wherein reducing the
particle dimension comprises grinding the solid mixture.
167. The method of embodiment 166, wherein grinding the solid
mixture comprises applying to the solid mixture at least one of a
mortar and a pestle, a jar mill, and a rock crusher.
168. The method of any one of embodiments 163 to 167, further
comprising extracting a component of the solid mixture having a
longest component dimension that is greater than a longest frustule
portion dimension of the plurality of diatom frustule portions.
169. The method of embodiment 168, wherein extracting the component
of the solid mixture comprises sieving the solid mixture.
170. The method of embodiment 169, wherein sieving the solid
mixture comprises processing the solid mixture with a sieve having
a mesh size from about 15 microns to about 25 microns.
171. The method of embodiment 169, wherein sieving the solid
mixture comprises processing the solid mixture with a sieve having
a mesh size from about 10 microns to about 25 microns.
172. The method of any one of embodiments 160 to 171, further
comprising sorting the plurality of diatom frustule portions to
separate a first diatom frustule portion from a second diatom
frustule portion, the first diatom frustule portion having a
greater longest dimension.
173. The method of embodiment 172, wherein the first diatom
frustule portion comprises a plurality of unbroken diatom frustule
portions.
174. The method of embodiment 172 or 173, wherein the second diatom
frustule portion comprises a plurality of broken diatom frustule
portions.
175. The method of any one of embodiments 172 to 174, wherein
sorting comprises filtering the plurality of diatom frustule
portions.
176. The method of embodiment 175, wherein filtering comprises
disturbing agglomeration of the plurality of diatom frustule
portions.
177. The method of embodiment 176, wherein disturbing agglomeration
of the plurality of diatom frustule portions comprises
stirring.
178. The method of embodiment 176 or 177, wherein disturbing
agglomeration of the plurality of diatom frustule portions
comprises shaking.
179. The method of any one of embodiments 176 to 178, wherein
disturbing agglomeration of the plurality of diatom frustule
portions comprises bubbling.
180. The method of any one of embodiments 175 to 179, wherein
filtering comprises applying a sieve to the plurality of diatom
frustule portions.
181. The method of embodiment 180, wherein the sieve has a mesh
size from about 5 microns to about 10 microns.
182. The method of embodiment 180, wherein the sieve has a mesh
size of about 7 microns.
183. The method of any one of embodiments 160 to 182, further
comprising obtaining a washed diatom frustule portion.
184. The method of embodiment 183, wherein obtaining the washed
diatom frustule portion comprises washing the plurality of diatom
frustule portions with a cleaning solvent after removing the at
least one of the organic contaminant and the inorganic
contaminant.
185. The method of embodiment 183 or 184, wherein obtaining the
washed diatom frustule portion comprises washing the diatom
frustule portion having the at least one common characteristic with
a cleaning solvent.
186. The method of embodiment 184 or 185, further comprising
removing the cleaning solvent.
187. The method of embodiment 186, wherein removing the cleaning
solvent comprises sedimenting the plurality of diatom frustule
portions after removing at least one of the organic contaminant and
the inorganic contaminant.
188. The method of embodiment 186 or 187, wherein removing the
cleaning solvent comprises sedimenting the plurality of diatom
frustule portions having the at least one common
characteristic.
189. The method of embodiment 187 or 188, wherein sedimenting
comprises centrifuging.
190. The method of embodiment 189, wherein centrifuging comprises
applying a centrifuge suitable for large scale processing.
191. The method of embodiment 190, wherein centrifuging comprises
applying at least one of a disc stack centrifuge, a decanter
centrifuge, and a tubular bowl centrifuge.
192. The method of any one of embodiments 184 to 191, wherein at
least one of the dispersing solvent and the cleaning solvent
comprises water.
193. The method of any one of embodiments 160 to 192, wherein at
least one of dispersing the plurality of diatom frustule portions
in the dispersing solvent and dispersing the plurality of diatom
frustule portions in the surfactant comprises sonicating the
plurality of diatom frustules.
194. The method of any one of embodiments 160 to 193, wherein the
surfactant comprises a cationic surfactant.
195. The method of embodiment 194, wherein the cationic surfactant
comprises at least one of a benzalkonium chloride, a cetrimonium
bromide, a lauryl methyl gluceth-10 hydroxypropyl dimonium
chloride, a benzethonium chloride, a benzethonium chloride, a
bronidox, a dmethyldioctadecylammonium chloride, and a
tetramethylammonium hydroxide.
196. The method of any one of embodiments 160 to 195, wherein the
surfactant comprises a non-ionic surfactant.
197. The method of embodiment 196, wherein the non-ionic surfactant
comprises at least one of a cetyl alcohol, a stearyl alcohol, a
cetostearyl alcohol, an oleyl alcohol, a polyoxyethylene glycol
alkyl ether, an octaethylene glycol monododecyl ether, a glucoside
alkyl ethers, a decyl glucoside, a polyoxyethylene glycol
octylphenol ethers, an octylphenol ethoxylate (Triton X-100.TM.), a
nonoxynol-9, a glyceryl laurate, a polysorbate, and a
poloxamer.
198. The method of any one of embodiments 160 to 197, further
comprising dispersing the plurality of diatom frustules in an
additive component.
199. The method of embodiment 198, wherein dispersing the plurality
of diatom frustules in an additive component is before dispersing
the plurality of diatom frustules in the surfactant.
200. The method of embodiment 198, wherein dispersing the plurality
of diatom frustules in an additive component is after dispersing
the plurality of diatom frustules in the surfactant.
201. The method of embodiment 198, wherein dispersing the plurality
of diatom frustules in an additive component is at least partially
simultaneous with dispersing the plurality of diatom frustules in
the surfactant.
202. The method of any one of embodiments 198 to 201, wherein the
additive component comprises at least one of a potassium chloride,
an ammonium chloride, an ammonium hydroxide, and a sodium
hydroxide.
203. The method of any one of embodiments 160 to 202, wherein
dispersing the plurality of diatom frustule portions comprises
obtaining a dispersion comprising about 1 weight percent to about 5
weight percent of the plurality of diatom frustule portions.
204. The method of any one of embodiments 160 to 203, wherein
removing the organic contaminant comprises heating the plurality of
diatom frustule portions in the presence of a bleach.
205. The method of embodiment 204, wherein the bleach comprises at
least one of a hydrogen peroxide and a nitric acid.
206. The method of embodiment 205, wherein heating comprises
heating the plurality of diatom frustule portions in a solution
comprising an amount of hydrogen peroxide in a range from about 10
volume percent to about 20 volume percent.
207. The method of any one of embodiments 204 to 206, wherein
heating comprises heating the plurality of diatom frustule portions
for a duration of about 5 minutes to about 15 minutes.
208. The method of any one of embodiments 160 to 207, wherein
removing the organic contaminant comprises annealing the plurality
of diatom frustule portions.
209. The method of any one of embodiments 160 to 208, wherein
removing the inorganic contaminant comprises combining the
plurality of diatom frustule portions with at least one of a
hydrochloric acid and a sulfuric acid.
210. The method of embodiment 209, wherein the combining comprises
mixing the plurality of diatom frustule portions in a solution
comprising about 15 volume percent to about 25 volume percent of
hydrochloric acid.
211. The method of embodiment 210, wherein the mixing is for a
duration of about 20 minutes to about 40 minutes.
212. A method of extracting a diatom frustule portion, the method
comprising: extracting a plurality of diatom frustule portions
having at least one common characteristic using a disc stack
centrifuge.
213. The method of embodiment 212, further comprising dispersing
the plurality of diatom frustule portions in a dispersing
solvent.
214. The method of embodiment 212 or 213, further comprising
removing at least one of an organic contaminant and an inorganic
contaminant.
215. The method of any one of embodiments 212 to 214, further
comprising dispersing the plurality of diatom frustule portions in
a surfactant, the surfactant reducing an agglomeration of the
plurality of diatom frustule portions.
216. The method of any one of embodiments 212 to 215, wherein the
at least one common characteristic comprises at least one of a
dimension, a shape, a material, and a degree of brokenness.
217. The method of embodiment 216, wherein the dimension comprises
at least one of a length and a diameter.
218. The method of any one of embodiments 212 to 217, wherein a
solid mixture comprises the plurality of diatom frustule
portions.
219. The method of embodiment 218, further comprising reducing a
particle dimension of the solid mixture.
220. The method of embodiment 219, wherein reducing the particle
dimension of the solid mixture is before dispersing the plurality
of diatom frustule portions in the dispersing solvent.
221. The method of embodiment 219 or 220, wherein reducing the
particle dimension comprises grinding the solid mixture.
222. The method of embodiment 221, wherein grinding the solid
mixture comprises applying to the solid mixture at least one of a
mortar and a pestle, a jar mill, and a rock crusher.
223. The method of any one of embodiments 219 to 222, further
comprising extracting a component of the solid mixture having a
longest component dimension that is greater than a longest frustule
portion dimension of the plurality of diatom frustule portions.
224. The method of embodiment 223, wherein extracting the component
of the solid mixture comprises sieving the solid mixture.
225. The method of embodiment 224, wherein sieving the solid
mixture comprises processing the solid mixture with a sieve having
a mesh size from about 15 microns to about 25 microns.
226. The method of embodiment 224, wherein sieving the solid
mixture comprises processing the solid mixture with a sieve having
a mesh size from about 10 microns to about 25 microns.
227. The method of any one of embodiments 212 to 226, further
comprising sorting the plurality of diatom frustule portions to
separate a first diatom frustule portion from a second diatom
frustule portion, the first diatom frustule portion having a
greater longest dimension.
228. The method of embodiment 227, wherein the first diatom
frustule portion comprises a plurality of unbroken diatom frustule
portions.
229. The method of embodiment 227 or 228, wherein the second diatom
frustule portion comprises a plurality of broken diatom frustule
portions.
230. The method of any one of embodiments 227 to 229, wherein
sorting comprises filtering the plurality of diatom frustule
portions.
231. The method of embodiment 230, wherein filtering comprises
disturbing agglomeration of the plurality of diatom frustule
portions.
232. The method of embodiment 231, wherein disturbing agglomeration
of the plurality of diatom frustule portions comprises
stirring.
233. The method of embodiment 231 or 282, wherein disturbing
agglomeration of the plurality of diatom frustule portions
comprises shaking.
234. The method of any one of embodiments 231 to 233, wherein
disturbing agglomeration of the plurality of diatom frustule
portions comprises bubbling.
235. The method of any one of embodiments 230 to 234, wherein
filtering comprises applying a sieve to the plurality of diatom
frustule portions.
236. The method of embodiment 235, wherein the sieve has a mesh
size from about 5 microns to about 10 microns.
237. The method of embodiment 235, wherein the sieve has a mesh
size of about 7 microns.
238. The method of any one of embodiments 212 to 237, further
comprising obtaining a washed diatom frustule portion.
239. The method of embodiment 238, wherein obtaining the washed
diatom frustule portion comprises washing the plurality of diatom
frustule portions with a cleaning solvent after removing at least
one of the organic contaminant and the inorganic contaminant.
240. The method of embodiment 238 or 239, wherein obtaining the
washed diatom frustule portion comprises washing the diatom
frustule portion having the at least one common characteristic with
a cleaning solvent.
241. The method of embodiment 239 or 240, further comprising
removing the cleaning solvent.
242. The method of embodiment 241, wherein removing the cleaning
solvent comprises sedimenting the plurality of diatom frustule
portions after removing the at least one of the organic contaminant
and the inorganic contaminant.
243. The method of embodiment 241 or 242, wherein removing the
cleaning solvent comprises sedimenting the plurality of diatom
frustule portions having the at least one common
characteristic.
244. The method of embodiment 242 or 243, wherein sedimenting
comprises centrifuging.
245. The method of embodiment 244, wherein centrifuging comprises
applying a centrifuge suitable for large scale processing.
246. The method of embodiment 245, wherein centrifuging comprises
applying at least one of a disc stack centrifuge, a decanter
centrifuge, and a tubular bowl centrifuge.
247. The method of any one of embodiments 240 to 246, wherein at
least one of the dispersing solvent and the cleaning solvent
comprises water.
248. The method of any one of embodiments 215 to 247, wherein at
least one of dispersing the plurality of diatom frustule portions
in the dispersing solvent and dispersing the plurality of diatom
frustule portions in the surfactant comprises sonicating the
plurality of diatom frustules.
249. The method of any one of embodiments 215 to 248, wherein the
surfactant comprises a cationic surfactant.
250. The method of embodiment 249, wherein the cationic surfactant
comprises at least one of a benzalkonium chloride, a cetrimonium
bromide, a lauryl methyl gluceth-10 hydroxypropyl dimonium
chloride, a benzethonium chloride, a benzethonium chloride, a
bronidox, a dmethyldioctadecylammonium chloride, and a
tetramethylammonium hydroxide.
251. The method of any one of embodiments 212 to 250, wherein the
surfactant comprises a non-ionic surfactant.
252. The method of embodiment 251, wherein the non-ionic surfactant
comprises at least one of a cetyl alcohol, a stearyl alcohol, a
cetostearyl alcohol, an oleyl alcohol, a polyoxyethylene glycol
alkyl ether, an octaethylene glycol monododecyl ether, a glucoside
alkyl ethers, a decyl glucoside, a polyoxyethylene glycol
octylphenol ethers, an octylphenol ethoxylate (Triton X-100.TM.), a
nonoxynol-9, a glyceryl laurate, a polysorbate, and a
poloxamer.
253. The method of any one of embodiments 212 to 252, further
comprising dispersing the plurality of diatom frustules in an
additive component.
254. The method of embodiment 253, wherein dispersing the plurality
of diatom frustules in an additive component is before dispersing
the plurality of diatom frustules in the surfactant.
255. The method of embodiment 253, wherein dispersing the plurality
of diatom frustules in an additive component is after dispersing
the plurality of diatom frustules in the surfactant.
256. The method of embodiment 253, wherein dispersing the plurality
of diatom frustules in an additive component is at least partially
simultaneous with dispersing the plurality of diatom frustules in
the surfactant.
257. The method of any one of embodiments 253 to 256, wherein the
additive component comprises at least one of a potassium chloride,
an ammonium chloride, an ammonium hydroxide, and a sodium
hydroxide.
258. The method of any one of embodiments 213 to 257, wherein
dispersing the plurality of diatom frustule portions in the
dispersing solvent comprises obtaining a dispersion comprising
about 1 weight percent to about 5 weight percent of the plurality
of diatom frustule portions.
259. The method of any one of embodiments 214 to 258, wherein
removing the organic contaminant comprises heating the plurality of
diatom frustule portions in the presence of a bleach.
260. The method of embodiment 259, wherein the bleach comprises at
least one of a hydrogen peroxide, and a nitric acid.
261. The method of embodiment 260, wherein heating comprises
heating the plurality of diatom frustule portions in a solution
comprising an amount of hydrogen peroxide in a range from about 10
volume percent to about 20 volume percent.
262. The method of any one of embodiments 259 to 261, wherein
heating comprises heating the plurality of diatom frustule portions
for a duration of about 5 minutes to about 15 minutes.
263. The method of any one of embodiments 214 to 262, wherein
removing the organic contaminant comprises annealing the plurality
of diatom frustule portions.
264. The method of any one of embodiments 214 to 263, wherein
removing the inorganic contaminant comprises combining the
plurality of diatom frustule portions with at least one of a
hydrochloric acid and a sulfuric acid.
265. The method of embodiment 264, wherein combining comprises
mixing the plurality of diatom frustule portions in a solution
comprising about 15 volume percent to about 25 volume percent of
hydrochloric acid.
266. The method of embodiment 265, wherein the mixing is for a
duration of about 20 minutes to about 40 minutes.
267. A method of extracting a diatom frustule portion, the method
comprising: dispersing a plurality of diatom frustule portions with
a surfactant, the surfactant reducing an agglomeration of the
plurality of diatom frustule portions.
268. The method of embodiment 267, further comprising extracting a
plurality of diatom frustule portions having at least one common
characteristic using a disc stack centrifuge.
269. The method of embodiment 267 or 268, further comprising
dispersing the plurality of diatom frustule portions in a
dispersing solvent.
270. The method of any one of embodiments 267 to 269, further
comprising removing at least one of an organic contaminant and an
inorganic contaminant.
271. The method of any one of embodiments 267 to 270, wherein the
at least one common characteristic comprises at least one of a
dimension, a shape, a material, and a degree of brokenness.
272. The method of embodiment 271, wherein the dimension comprises
at least one of a length and a diameter.
273. The method of any one of embodiments 267 to 272, wherein a
solid mixture comprises the plurality of diatom frustule
portions.
274. The method of embodiment 273, further comprising reducing a
particle dimension of the solid mixture.
275. The method of embodiment 274, wherein reducing the particle
dimension of the solid mixture is before dispersing the plurality
of diatom frustule portions in the dispersing solvent.
276. The method of embodiment 274 or 275, wherein reducing the
particle dimension comprises grinding the solid mixture.
277. The method of embodiment 276, wherein grinding the solid
mixture comprises applying to the solid mixture at least one of a
mortar and a pestle, a jar mill, and a rock crusher.
278. The method of any one of embodiments 273 to 277, further
comprising extracting a component of the solid mixture having a
longest component dimension that is greater than a longest frustule
portion dimension of the plurality of diatom frustule portions.
279. The method of embodiment 278, wherein extracting the component
of the solid mixture comprises sieving the solid mixture.
280. The method of embodiment 279, wherein sieving the solid
mixture comprises processing the solid mixture with a sieve having
a mesh size from about 15 microns to about 25 microns.
281. The method of embodiment 279, wherein sieving the solid
mixture comprises processing the solid mixture with a sieve having
a mesh size from about 10 microns to about 25 microns.
282. The method of any one of embodiments 267 to 281, further
comprising sorting the plurality of diatom frustule portions to
separate a first diatom frustule portion from a second diatom
frustule portion, the first diatom frustule portion having a
greater longest dimension.
283. The method of embodiment 282, wherein the first diatom
frustule portion comprises a plurality of unbroken diatom frustule
portions.
284. The method of embodiment 282 or 283, wherein the second diatom
frustule portion comprises a plurality of broken diatom frustule
portions.
285. The method of any one of embodiments 282 to 284, wherein
sorting comprises filtering the plurality of diatom frustule
portions.
286. The method of embodiment 285, wherein filtering comprises
disturbing agglomeration of the plurality of diatom frustule
portions.
287. The method of embodiment 286, wherein disturbing agglomeration
of the plurality of diatom frustule portions comprises
stirring.
288. The method of embodiment 286 or 287, wherein disturbing
agglomeration of the plurality of diatom frustule portions
comprises shaking.
289. The method of any one of embodiments 286 to 288, wherein
disturbing agglomeration of the plurality of diatom frustule
portions comprises bubbling.
290. The method of any one of embodiments 285 to 289, wherein
filtering comprises applying a sieve to the plurality of diatom
frustule portions.
291. The method of embodiment 290, wherein the sieve has a mesh
size from about 5 microns to about 10 microns.
292. The method of embodiment 290, wherein the sieve has a mesh
size of about 7 microns.
293. The method of any one of embodiments 267 to 292, further
comprising obtaining a washed diatom frustule portion.
294. The method of embodiment 293, wherein obtaining the washed
diatom frustule portion comprises washing the plurality of diatom
frustule portions with a cleaning solvent after removing the at
least one of the organic contaminant and the inorganic
contaminant.
295. The method of embodiment 293 or 294 wherein obtaining the
washed diatom frustule portion comprises washing the diatom
frustule portion having the at least one common characteristic with
a cleaning solvent.
296. The method of embodiment 294 or 295, further comprising
removing the cleaning solvent.
297. The method of embodiment 296, wherein removing the cleaning
solvent comprises sedimenting the plurality of diatom frustule
portions after removing the at least one of the organic contaminant
and the inorganic contaminant.
298. The method of embodiment 296 or 297, wherein removing the
cleaning solvent comprises sedimenting the plurality of diatom
frustule portions having the at least one common
characteristic.
299. The method of embodiment 297 or 298, wherein sedimenting
comprises centrifuging.
300. The method of embodiment 299, wherein centrifuging comprises
applying a centrifuge suitable for large scale processing.
301. The method of embodiment 300, wherein centrifuging comprises
applying at least one of a disc stack centrifuge, a decanter
centrifuge, and a tubular bowl centrifuge.
302. The method of any one of embodiments 295 to 301, wherein at
least one of the dispersing solvent and the cleaning solvent
comprises water.
303. The method of any one of embodiments 269 to 302, wherein at
least one of dispersing the plurality of diatom frustule portions
in the dispersing solvent and dispersing the plurality of diatom
frustule portions in the surfactant comprises sonicating the
plurality of diatom frustules.
304. The method of any one of embodiments 267 to 303, wherein the
surfactant comprises a cationic surfactant.
305. The method of embodiment 304, wherein the cationic surfactant
comprises at least one of a benzalkonium chloride, a cetrimonium
bromide, a lauryl methyl gluceth-10 hydroxypropyl dimonium
chloride, a benzethonium chloride, a benzethonium chloride, a
bronidox, a dmethyldioctadecylammonium chloride, and a
tetramethylammonium hydroxide.
306. The method of any one of embodiments 267 to 305, wherein the
surfactant comprises a non-ionic surfactant.
307. The method of embodiment 306, wherein the non-ionic surfactant
comprises at least one of a cetyl alcohol, a stearyl alcohol, a
cetostearyl alcohol, an oleyl alcohol, a polyoxyethylene glycol
alkyl ether, an octaethylene glycol monododecyl ether, a glucoside
alkyl ethers, a decyl glucoside, a polyoxyethylene glycol
octylphenol ethers, an octylphenol ethoxylate (Triton X-100.TM.), a
nonoxynol-9, a glyceryl laurate, a polysorbate, and a
poloxamer.
308. The method of any one of embodiments 267 to 307, further
comprising dispersing the plurality of diatom frustules in an
additive component.
309. The method of embodiment 308, wherein dispersing the plurality
of diatom frustules in an additive component is before dispersing
the plurality of diatom frustules in the surfactant.
310. The method of embodiment 308, wherein dispersing the plurality
of diatom frustules in an additive component is after dispersing
the plurality of diatom frustules in the surfactant.
311. The method of embodiment 308, wherein dispersing the plurality
of diatom frustules in an additive component is at least partially
simultaneous with dispersing the plurality of diatom frustules in
the surfactant.
312. The method of any one of embodiments 308 to 311, wherein the
additive component comprises at least one of a potassium chloride,
an ammonium chloride, an ammonium hydroxide, and a sodium
hydroxide.
313. The method of any one of embodiments 269 to 312, wherein
dispersing the plurality of diatom frustule portions in the
dispersing solvent comprises obtaining a dispersion comprising
about 1 weight percent to about 5 weight percent of the plurality
of diatom frustule portions.
314. The method of any one of embodiments 270 to 313, wherein
removing the organic contaminant comprises heating the plurality of
diatom frustule portions in the presence of a bleach.
315. The method of embodiment 314, wherein the bleach comprises at
least one of a hydrogen peroxide, and a nitric acid.
316. The method of embodiment 315, wherein heating comprises
heating the plurality of diatom frustule portions in a solution
comprising an amount of hydrogen peroxide in a range from about 10
volume percent to about 20 volume percent.
317. The method of any one of embodiments 314 to 316, wherein
heating comprises heating the plurality of diatom frustule portions
for a duration of about 5 minutes to about 15 minutes.
318. The method of any one of embodiments 270 to 317, wherein
removing the organic contaminant comprises annealing the plurality
of diatom frustule portions.
319. The method of any one of embodiments 270 to 218, wherein
removing the inorganic contaminant comprises combining the
plurality of diatom frustule portions with at least one of a
hydrochloric acid and a sulfuric acid.
320. The method of embodiment 319, wherein combining comprises
mixing the plurality of diatom frustule portions in a solution
comprising about 15 volume percent to about 25 volume percent of
hydrochloric acid.
321. The method of embodiment 320, wherein the mixing is for a
duration of about 20 minutes to about 40 minutes.
322. A method of forming silver nanostructures on a diatom frustule
portion, the method comprising: forming a silver seed layer on a
surface of the diatom frustule portion; and forming a nanostructure
on the seed layer.
323. The method of embodiment 322, wherein the nanostructures
comprises at least one of a coating, a nanowire, a nanoplate, a
dense array of nanoparticles, a nanobelt, and a nanodisk.
324. The method of embodiment 322 or 323, wherein the
nanostructures comprises silver.
325. The method of any one of embodiment 322 to 324, wherein
forming the silver seed layer comprises applying a cyclic heating
regimen to a first silver contributing component and the diatom
frustule portion.
326. The method of embodiment 325, wherein applying the cyclic
heating regimen comprises applying a cyclic microwave power.
327. The method of embodiment 326, wherein applying the cyclic
microwave power comprises alternating a microwave power between
about 100 Watt and 500 Watt.
328. The method of embodiment 327, wherein alternating comprises
alternating the microwave power every minute.
329. The method of embodiment 327 or 328, wherein alternating
comprises alternating the microwave power for a duration of about
30 minutes.
330. The method of embodiment 327 or 328, wherein alternating
comprises alternating the microwave power for a duration of about
20 minutes to about 40 minutes.
331. The method of any one of embodiments 322 to 330, wherein
forming the silver seed layer comprises combining the diatom
frustule portion with a seed layer solution.
332. The method of embodiment 331, wherein the seed layer solution
comprises the first silver contributing component and a seed layer
reducing agent.
333. The method of embodiment 332, wherein the seed layer reducing
agent is a seed layer solvent.
334. The method of embodiment 333, wherein the seed layer reducing
agent and the seed layer solvent comprises a polyethylene
glycol.
335. The method of embodiment 331, wherein the seed layer solution
comprises the first silver contributing component, a seed layer
reducing agent and a seed layer solvent.
336. The method of any one of embodiments 331 to 335, wherein
forming the silver seed layer further comprises mixing the diatom
frustule portion with the seed layer solution.
337. The method of embodiment 336, wherein mixing comprises
ultrasonicating.
338. The method of embodiment 337, wherein the seed layer reducing
agent comprises a N,N-Dimethylformamide, the first silver
contributing component comprises a silver nitrate, and the seed
layer solvent comprises at least one of a water and a
polyvinylpyrrolidone.
339. The method of any one of embodiments 322 to 338, wherein
forming the nanostructure comprises combining the diatom frustule
portion with a nanostructure forming reducing agent.
340. The method of embodiment 339, wherein forming the
nanostructure further comprises heating the diatom frustule portion
after combining the diatom frustule portion with the nanostructure
forming reducing agent.
341. The method of embodiment 340, wherein heating comprises
heating to a temperature of about 120.degree. C. to about
160.degree. C.
342. The method of embodiment 340 or 341, wherein forming the
nanostructure further comprises titrating the diatom frustule
portion with a titration solution comprising a nanostructure
forming solvent and a second silver contributing component.
343. The method of embodiment 342, wherein forming the
nanostructure further comprises mixing after titrating the diatom
frustule portion with the titration solution.
344. The method of any one of embodiments 339 to 343, wherein at
least one of the seed layer reducing agent and the nanostructure
forming reducing agent comprises at least one of a hydrazine, a
formaldehyde, a glucose, sodium tartrate, an oxalic acid, a formic
acid, an ascorbic acid, and an ethylene glycol.
345. The method of any one of embodiments 342 to 344, wherein at
least one of the first silver contributing component and the second
silver contributing component comprises at least one of a silver
salt and a silver oxide.
346. The method of embodiment 345, wherein the silver salt
comprises at least one of a silver nitrate and an ammoniacal silver
nitrate, a silver chloride (AgCl), a silver cyanide (AgCN), a
silver tetrafluoroborate, a silver hexafluorophosphate, and a
silver ethylsulphate.
347. The method of any one of embodiments 322 to 346, wherein
forming the nanostructure is in an ambient to reduce oxide
formation.
348. The method of embodiment 347, wherein the ambient comprises an
argon atmosphere.
349. The method of any one of embodiments 342 to 348, wherein at
least one of the seed layer solvent and the nanostructure forming
solvent comprises at least one of a propylene glycol, a water, a
methanol, an ethanol, a 1-propanol, a 2-propanol a
1-methoxy-2-propanol, a 1-butanol, a 2-butanol a 1-pentanol, a
2-pentanol, a 3-pentanol, a 1-hexanol, a 2-hexanol, a 3-hexanol, an
octanol, a 1-octanol, a 2-octanol, a 3-octanol, a
tetrahydrofurfuryl alcohol (THFA), a cyclohexanol, a cyclopentanol,
a terpineol, a butyl lactone; a methyl ethyl ether, a diethyl
ether, an ethyl propyl ether, a polyethers, a diketones, a
cyclohexanone, a cyclopentanone, a cycloheptanone, a cyclooctanone,
an acetone, a benzophenone, an acetylacetone, an acetophenone, a
cyclopropanone, an isophorone, a methyl ethyl ketone, an ethyl
acetate, a dimethyl adipate, a propylene glycol monomethyl ether
acetate, a dimethyl glutarate, a dimethyl succinate, a glycerin
acetate, a carboxylates, a propylene carbonate, a glycerin, a diol,
a triol, a tetraol, a pentanol, an ethylene glycol, a diethylene
glycol, a polyethylene glycol, a propylene glycol, a dipropylene
glycol, a glycol ether, a glycol ether acetate, a 1,4-butanediol, a
1,2-butanediol, a 2,3-butanediol, a 1,3-propanediol, a
1,4-butanediol, a 1,5-pentanediol, a 1,8-octanediol, a
1,2-propanediol, a 1,3-butanediol, a 1,2-pentanediol, an
etohexadiol, a p-menthane-3,8-diol, a 2-methyl-2,4-pentanediol, a
tetramethyl urea, a n-methylpyrrolidone, an acetonitrile, a
tetrahydrofuran (THF), a dimethyl formamide (DMF), a N-methyl
formamide (NMF), a dimethyl sulfoxide (DMSO), a thionyl chloride
and a sulfuryl chloride.
350. The method of any one of embodiments 322 to 349, wherein the
diatom frustule portion comprises a broken diatom frustule
portion.
351. The method of any one of embodiments 322 to 349, wherein the
diatom frustule portion comprises an unbroken diatom frustule
portion.
352. The method of any one of embodiments 322 to 351, wherein the
diatom frustule portion is obtained through a diatom frustule
portion separation process.
353. The method of embodiment 352, wherein the process comprises at
least one of using a surfactant to reduce an agglomeration of a
plurality of diatom frustule portions and using a disc stack
centrifuge.
354. A method of forming zinc-oxide nanostructures on a diatom
frustule portion, the method comprising: forming a zinc-oxide seed
layer on a surface of the diatom frustule portion; and forming a
nanostructure on the zinc-oxide seed layer.
355. The method of embodiment 354, wherein the nanostructure
comprises at least one of a nanowire, a nanoplate, a dense array of
nanoparticles, a nanobelt, and a nanodisk.
356. The method of embodiment 354 or 355, wherein the
nanostructures comprises zinc-oxide.
357. The method of any one of embodiments 354 to 356, wherein
forming the zinc-oxide seed layer comprises heating a first zinc
contributing component and the diatom frustule portion.
358. The method of embodiment 357, wherein heating the first zinc
contributing component and the diatom frustule portion comprises
heating to a temperature in a range from about 175.degree. C. to
about 225.degree. C.
359. The method of any one of embodiments 354 to 358, wherein
forming the nanostructure comprises applying a heating regimen to
the diatom frustule portion having the zinc-oxide seed layer in the
presence of a nanostructure forming solution comprising a second
zinc contributing component.
360. The method of embodiment 359, wherein the heating regimen
comprises heating to a nanostructure forming temperature.
361. The method of embodiment 360, wherein the nanostructure
forming temperature is from about 80.degree. C. to about
100.degree. C.
362. The method of embodiment 360 or 361, wherein the heating is
for a duration of about one to about three hours.
363. The method of any one of embodiments 359 to 362, wherein the
heating regimen comprises applying a cyclic heating routine.
364. The method of embodiment 363, wherein the cyclic heating
routine comprises applying a microwave heating to the diatom
frustule portion having the zinc-oxide seed layer for a heating
duration and then turning the microwaving heating off for a cooling
duration, for a total cyclic heating duration.
365. The method of embodiment 364, wherein the heating duration is
about 1 minute to about 5 minutes.
366. The method of embodiment 364 or 365, wherein the cooling
duration is about 30 seconds to about 5 minutes.
367. The method of any one of embodiments 364 to 366, wherein the
total cyclic heating duration is about 5 minutes to about 20
minutes.
368. The method of any one of embodiments 364 to 367, wherein
applying the microwave heating comprises applying about 480 Watt to
about 520 Watt of microwave power.
369. The method of any one of embodiments 364 to 367, wherein
applying the microwave heating comprises applying about 80 Watt to
about 120 Watt of microwave power.
370. The method of any one of embodiments 359 to 369, wherein at
least one of the first zinc contributing component and the second
zinc contributing component comprise at least one of a zinc
acetate, a zinc acetate hydrate, a zinc nitrate, a zinc nitrate
hexahydrate, a zinc chloride, a zinc sulfate, and a sodium
zincate.
371. The method of any one of embodiments 359 to 370, wherein the
nanostructure forming solution comprises a base.
372. The method of embodiment 371, wherein the base comprises at
least one of a sodium hydroxide, an ammonium hydroxide, potassium
hydroxide, a teramethylammonium hydroxide, a lithium hydroxide, a
hexamethylenetetramine, an ammonia solution, a sodium carbonate,
and a ethylenediamine.
373. The method of any one of embodiments 354 to 372, wherein
forming the nanostructure further comprises adding an additive
component.
374. The method of embodiment 373, wherein the additive component
comprises at least one of a tributylamine, a triethylamine, a
triethanolamine, a diisopropylamine, an ammonium phosphate, a
1,6-hexadianol, a triethyldiethylnol, an isopropylamine, a
cyclohexylamine, a n-butylamine, an ammonium chloride, a
hexamethylenetetramine, an ethylene glycol, an ethanoamine, a
polyvinylalcohol, a polyethylene glycol, a sodium dodecyl sulphate,
a cetyltrimethyl ammonium bromide, and a carbamide.
375. The method of any one of embodiments 359 to 374, wherein at
least one of the nanostructure forming solution and a zinc-oxide
seed layer forming solution comprises a solvent, the solvent
comprising at least one of a propylene glycol, a water, a methanol,
an ethanol, a 1-propanol, a 2-propanol a 1-methoxy-2-propanol, a
1-butanol, a 2-butanol a 1-pentanol, a 2-pentanol, a 3-pentanol, a
1-hexanol, a 2-hexanol, a 3-hexanol, an octanol, a 1-octanol, a
2-octanol, a 3-octanol, a tetrahydrofurfuryl alcohol (THFA), a
cyclohexanol, a cyclopentanol, a terpineol, a butyl lactone; a
methyl ethyl ether, a diethyl ether, an ethyl propyl ether, a
polyethers, a diketones, a cyclohexanone, a cyclopentanone, a
cycloheptanone, a cyclooctanone, an acetone, a benzophenone, an
acetylacetone, an acetophenone, a cyclopropanone, an isophorone, a
methyl ethyl ketone, an ethyl acetate, a dimethyl adipate, a
propylene glycol monomethyl ether acetate, a dimethyl glutarate, a
dimethyl succinate, a glycerin acetate, a carboxylates, a propylene
carbonate, a glycerin, a diol, a triol, a tetraol, a pentanol, an
ethylene glycol, a diethylene glycol, a polyethylene glycol, a
propylene glycol, a dipropylene glycol, a glycol ether, a glycol
ether acetate, a 1,4-butanediol, a 1,2-butanediol, a
2,3-butanediol, a 1,3-propanediol, a 1,4-butanediol, a
1,5-pentanediol, a 1,8-octanediol, a 1,2-propanediol, a
1,3-butanediol, a 1,2-pentanediol, an etohexadiol, a
p-menthane-3,8-diol, a 2-methyl-2,4-pentanediol, a tetramethyl
urea, a n-methylpyrrolidone, an acetonitrile, a tetrahydrofuran
(THF), a dimethyl formamide (DMF), a N-methyl formamide (NMF), a
dimethyl sulfoxide (DMSO), a thionyl chloride and a sulfuryl
chloride.
376. The method of any one of embodiments 354 to 375, wherein the
diatom frustule portion comprises a broken diatom frustule
portion.
377. The method of any one of embodiments 354 to 375, wherein the
diatom frustule portion comprises an unbroken diatom frustule
portion.
378. The method of any one of embodiments 354 to 375, wherein the
diatom frustule portion is obtained through a diatom frustule
portion separation process.
379. The method of embodiment 378, wherein the process comprises at
least one of using a surfactant to reduce an agglomeration of a
plurality of diatom frustule portions and using a disc stack
centrifuge.
380. A method of forming carbon nanostructures on a diatom frustule
portion, the method comprising: forming a metal seed layer on a
surface of the diatom frustule portion; and forming a carbon
nanostructure on the seed layer.
381. The method of embodiment 380, wherein the carbon nanostructure
comprises a carbon nanotube.
382. The method of embodiment 381, wherein the carbon nanotube
comprise at least one of a single-walled carbon nanotube and a
multi-walled carbon nanotube.
383. The method of any one of embodiments 380 to 382, wherein
forming the metal seed layer comprises spray coating the surface of
the diatom frustule portion.
384. The method of any one of embodiments 380 to 383, wherein
forming the metal seed layer comprises introducing the surface of
the diatom frustule portion to at least one of a liquid comprising
the metal, a gas comprising the metal and the solid comprising a
metal.
385. The method of any one of embodiments 380 to 384, wherein
forming the carbon nanostructure comprises using chemical vapor
deposition (CVD).
386. The method of any one of embodiments 380 to 385, wherein
forming the carbon nanostructure comprises exposing the diatom
frustule portion to a nanostructure forming reducing gas after
exposing the diatom frustule portion to a nanostructure forming
carbon gas.
387. The method of any one of embodiments 380 to 385, wherein
forming the carbon nanostructure comprises exposing the diatom
frustule portion to a nanostructure forming reducing gas before
exposing the diatom frustule portion to a nanostructure forming
carbon gas.
388. The method of any one of embodiments 380 to 385, wherein
forming the carbon nanostructure comprises exposing the diatom
frustule portion to a nanostructure forming gas mixture comprising
a nanostructure forming reducing gas and a nanostructure forming
carbon gas.
389. The method of embodiment 388, wherein the nanostructure
forming gas mixture further comprises a neutral gas.
390. The method of embodiment 389, wherein the neutral gas
comprises argon.
391. The method of any one of embodiments 380 to 390, wherein the
metal comprises at least one of a nickel, an iron, a cobalt, a
cobalt-molibdenium bimetallic, a copper, a gold, a silver, a
platinum, a palladium, a manganese, an aluminum, a magnesium, a
chromium, an antimony, an aluminum-iron-molybdenum (Al/Fe/Mo), an
iron pentacarbonyl (Fe(CO).sub.5)), an iron (III) nitrate
hexahydrate ((Fe(NO.sub.3).sub.3.6H.sub.2O), a colbalt (II)
chloride hexahydrate (CoCl.sub.2.6H.sub.2O), an ammonium molybdate
tetrahydrate ((NH.sub.4).sub.6Mo.sub.7O.sub.24.4H.sub.2O), a
molybdenum (VI) dichloride dioxide MoO.sub.2Cl.sub.2, and an
alumina nanopowder.
392. The method of any one of embodiments 286 to 391, wherein the
nanostructure forming reducing gas comprises at least one of an
ammonia, a nitrogen, and a hydrogen.
393. The method of any one of embodiments 286 to 392, wherein the
nanostructure forming carbon gas comprises at least one of an
acetylene, an ethylene, an ethanol, a methane, a carbon oxide, and
a benzene.
394. The method of any one of embodiments 380 to 393, wherein
forming the metal seed layer comprises forming a silver seed
layer.
395. The method of embodiment 394, wherein forming the silver seed
layer comprises forming a silver nanostructure on the surface of
the diatom frustule portion.
396. The method of any one of embodiments 380 to 395, wherein the
diatom frustule portion comprises a broken diatom frustule
portion.
397. The method of any one of embodiments 380 to 395, wherein the
diatom frustule portion comprises an unbroken diatom frustule
portion.
398. The method of any one of embodiments 380 to 397, wherein the
diatom frustule portion is obtained through a diatom frustule
portion separation process.
399. The method of embodiment 398, wherein the process comprises at
least one of using a surfactant to reduce an agglomeration of a
plurality of diatom frustule portions and using a disc stack
centrifuge.
400. A method of fabricating a silver ink, the method comprising:
combining an ultraviolet light sensitive component and a plurality
of diatom frustule portions having a silver nanostructure on a
surface of the plurality of diatom frustule portions, the surface
comprising a plurality of perforations.
401. The method of embodiment 400, further comprising forming a
silver seed layer on the surface of the plurality of diatom
frustule portions.
402. The method of embodiment 400 or 401, further comprising
forming the silver nanostructure on the seed layer.
403. The method of any one of embodiments 400 to 402, wherein the
plurality of diatom frustule portions comprises a plurality of
broken diatom frustule portions.
404. The method of any one of embodiments 400 to 403, wherein the
plurality of diatom frustule portions comprises a plurality of
diatom frustule flakes.
405. The method of any one of embodiments 400 to 404, wherein the
silver ink is depositable in a layer having a thickness of about 5
microns to about 15 microns after curing.
406. The method of any one of embodiments 400 to 405, wherein at
least one of the plurality of perforations comprises a diameter of
about 250 nanometers to about 350 nanometers.
407. The method of any one of embodiments 400 to 406, wherein the
silver nanostructure comprises a thickness of about 10 nanometers
to about 500 nanometers.
408. The method of any one of embodiments 400 to 407, wherein the
silver ink comprises an amount of diatom frustules within a range
of about 50 weight percent to about 80 weight percent.
409. The method of any one of embodiments 401 to 408, wherein
forming the silver seed layer comprises forming the silver seed
layer on a surface within the plurality of perforations to form a
plurality of silver seed plated perforations.
410. The method of any one of embodiments 401 to 409, wherein
forming the silver seed layer comprises forming the silver seed
layer on substantially all surfaces of the plurality of diatom
frustule portions.
411. The method of any one of embodiments 402 to 410, wherein
forming the silver nanostructure comprises forming the silver
nanostructure on a surface within the plurality of perforations to
form a plurality of silver nanostructure plated perforations.
412. The method of any one of embodiments 402 to 411, wherein
forming the silver nanostructure comprises forming the silver
nanostructure on substantially all surfaces of the plurality of
diatom frustule portions.
413. The method of any one of embodiments 400 to 412, wherein the
ultraviolet light sensitive component is sensitive to an optical
radiation having a wavelength shorter than a dimension of the
plurality of perforations.
414. The method of any one of embodiments 411 to 413, wherein the
ultraviolet light sensitive component is sensitive to an optical
radiation having a wavelength shorter than a dimension of at least
one of the plurality of silver seed plated perforations and the
plurality of silver nanostructure plated perforations.
415. The method of any one of embodiments 400 to 414, wherein
combining the plurality of diatom frustule portions with the
ultraviolet light sensitive component comprises combining the
plurality of diatom frustule portions with a photoinitiation
synergist agent.
416. The method of embodiment 415, wherein the photoinitiation
synergist agent comprises at least one of an ethoxylated hexanediol
acrylate, a propoxylated hexanediol acrylate, an ethoxylated
trimethylpropane triacrylate, a triallyl cyanurate and an acrylated
amine.
417. The method of any one of embodiments 400 to 416, wherein
combining the plurality of diatom frustule portions with the
ultraviolet light sensitive component comprises combining the
plurality of diatom frustule portions with a photoinitiator
agent.
418. The method of embodiment 417, wherein the photoinitiator agent
comprises at least one of a
2-methyl-1-(4-methylthio)phenyl-2-morpholinyl-1-propanon and an
isopropyl thioxothanone.
419. The method of any one of embodiments 400 to 418, wherein
combining the plurality of diatom frustule portions with the
ultraviolet light sensitive component comprises combining the
plurality of diatom frustule portions with a polar vinyl
monomer.
420. The method of embodiment 419, wherein the polar vinyl monomer
comprises at least one of a n-vinyl-pyrrolidone and a
n-vinylcaprolactam.
421. The method of any one of embodiments 400 to 420, further
comprising combining the plurality of diatom frustule portions with
a rheology modifying agent.
422. The method of any one of embodiments 400 to 421, further
comprising combining the plurality of diatom frustule portions with
a crosslinking agent.
423. The method of any one of embodiments 400 to 422, further
comprising combining the plurality of diatom frustule portions with
a flow and level agent.
424. The method of any one of embodiments 400 to 423, further
comprising combining the plurality of diatom frustule portions with
at least one of an adhesion promoting agent, a wetting agent, and a
viscosity reducing agent.
425. The method of any one of embodiments 400 to 424, wherein the
silver nanostructure comprises at least one of a coating, a
nanowire, a nanoplate, a dense array of nanoparticles, a nanobelt,
and a nanodisk.
426. The method of any one of embodiment 401 to 425, wherein
forming the silver seed layer comprises applying a cyclic heating
regimen to a first silver contributing component and the plurality
of diatom frustule portions.
427. The method of any one of embodiments 401 to 426, wherein
forming the silver seed layer comprises combining the diatom
frustule portion with a seed layer solution.
428. The method of embodiment 427, wherein the seed layer solution
comprises the first silver contributing component and a seed layer
reducing agent.
429. The method of any one of embodiments 402 to 428, wherein
forming the silver nanostructure comprises combining the diatom
frustule portion with a nanostructure forming reducing agent.
430. The method of embodiment 429, wherein forming the silver
nanostructure further comprises heating the diatom frustule portion
after combining the diatom frustule portion with the nanostructure
forming reducing agent.
431. The method of any one of embodiments 402 to 430, wherein
forming the silver nanostructure further comprises titrating the
diatom frustule portion with a titration solution comprising a
nanostructure forming solvent and a second silver contributing
component.
432. The method of any one of embodiments 400 to 431, wherein the
plurality of diatom frustule portions are obtained through a diatom
frustule portion separation process.
433. The method of embodiment 432, wherein the process comprises at
least one of using a surfactant to reduce an agglomeration of a
plurality of diatom frustule portions and using a disc stack
centrifuge.
434. A conductive silver ink comprising: an ultraviolet light
sensitive component; and a plurality of diatom frustule portions
having a silver nanostructure on a surface of the plurality of
diatom frustule portions, the surface comprising a plurality of
perforations.
435. The conductive silver ink of embodiment 434, wherein the
plurality of diatom frustule portions comprises a plurality of
broken diatom frustule portion.
436. The conductive silver ink of embodiment 434 or 435, wherein
the plurality of diatom frustule portions comprises a plurality of
diatom frustule flakes.
437. The conductive silver ink of any one of embodiments 434 to
436, wherein the silver ink is depositable in a layer having a
thickness of about 5 microns to about 15 microns after curing.
438. The conductive silver ink of any one of embodiments 434 to
437, wherein at least one of the plurality of perforations
comprises a diameter of about 250 nanometers to about 350
nanometers.
439. The conductive silver ink of any one of embodiments 434 to
438, wherein the silver nanostructure comprises a thickness of
about 10 nanometers to about 500 nanometers.
440. The conductive silver ink of any one of embodiments 434 to
439, wherein the silver ink comprises an amount of diatom frustules
within a range of about 50 weight percent to about 80 weight
percent.
441. The conductive silver ink of any one of embodiments 434 to
440, wherein at least one of the plurality of perforations
comprises a surface having a silver nanostructure.
442. The conductive silver ink of any one of embodiments 434 to
441, wherein at least one of the plurality of perforations
comprises a surface having a silver seed layer.
443. The conductive silver ink of any one of embodiments 434 to
442, wherein substantially all surfaces of the plurality of diatom
frustule portions comprises a silver nanostructure.
444. The conductive silver ink of any one of embodiments 434 to
443, wherein the ultraviolet light sensitive component is sensitive
to an optical radiation having a wavelength shorter than a
dimension of the plurality of perforations.
445. The conductive silver ink of any one of embodiments 434 to
444, wherein the conductive silver ink is curable by an ultraviolet
radiation.
446. The conductive silver ink of embodiment 445, wherein the
conductive silver ink is curable when deposited in a layer having a
thickness of about 5 microns to about 15 microns after curing.
447. The conductive silver ink of embodiment 445 or 446, wherein
the plurality of perforations has a dimension configured to allow
the ultraviolet radiation to pass through the plurality of diatom
frustule portions.
448. The conductive silver ink of any one of embodiments 434 to
447, wherein the conductive silver ink is thermally curable.
449. The conductive silver ink of any one of embodiments 434 to
448, wherein the ultraviolet light sensitive component comprises a
photoinitiation synergist agent.
450. The conductive silver ink of embodiment 449, wherein the
photoinitiation synergist agent comprises at least one of an
ethoxylated hexanediol acrylate, a propoxylated hexanediol
acrylate, an ethoxylated trimethylpropane triacrylate, a triallyl
cyanurate and an acrylated amine.
451. The conductive silver ink of any one of embodiments 434 to
450, wherein the ultraviolet light sensitive component comprises a
photoinitiator agent.
452. The conductive silver ink of embodiment 451, wherein the
photoinitiator agent comprises at least one of a
2-methyl-1-(4-methylthio)phenyl-2-morpholinyl-1-propanon and an
isopropyl thioxothanone.
453. The conductive silver ink of any one of embodiments 434 to
452, wherein the ultraviolet light sensitive component comprises a
polar vinyl monomer.
454. The conductive silver ink of embodiment 453, wherein the polar
vinyl monomer comprises at least one of a n-vinyl-pyrrolidone and a
n-vinylcaprolactam.
455. The conductive silver ink of any one of embodiments 434 to
454, further comprising at least one of a rheology modifying agent,
a crosslinking agent, a flow and level agent, an adhesion promoting
agent, a wetting agent, and a viscosity reducing agent.
456. The conductive silver ink of any one of embodiments 434 to
455, wherein the silver nanostructure comprises at least one of a
coating, a nanowire, a nanoplate, a dense array of nanoparticles, a
nanobelt, and a nanodisk.
457. A method of fabricating a silver film, the method comprising:
curing a mixture comprising an ultraviolet light sensitive
component and a plurality of diatom frustule portions having a
silver nanostructure on a surface of the plurality of diatom
frustule portions, the surface comprising a plurality of
perforations.
458. The method of embodiment 457, further comprising forming a
silver seed layer on the surface of the plurality of diatom
frustule portions.
459. The method of embodiment 457 or 458, further comprising
forming the silver nanostructure on the seed layer.
460. The method of any one of embodiments 457 to 459, further
comprising combining the plurality of diatom frustule portions with
the ultraviolet light sensitive component to form a silver ink.
461. The method of any one of embodiments 457 to 460, wherein the
plurality of diatom frustule portions comprises a plurality of
broken diatom frustule portions.
462. The method of any one of embodiments 457 to 461, wherein the
plurality of diatom frustule portions comprises a plurality of
diatom frustule flakes.
463. The method of any one of embodiments 460 to 462, wherein the
silver ink is depositable in a layer having a thickness of about 5
microns to about 15 microns after curing.
464. The method of any one of embodiments 457 to 463, wherein at
least one of the plurality of perforations comprises a diameter of
about 250 nanometers to about 350 nanometers.
465. The method of any one of embodiments 457 to 464, wherein the
silver nanostructure comprises a thickness of about 10 nanometers
to about 500 nanometers.
466. The method of any one of embodiments 460 to 465, wherein the
silver ink comprises an amount of diatom frustules within a range
of about 50 weight percent to about 80 weight percent.
467. The method of any one of embodiments 458 to 466, wherein
forming the silver seed layer comprises forming the silver seed
layer on a surface within the plurality of perforations to form a
plurality of silver seed plated perforations.
468. The method of any one of embodiments 458 to 467, wherein
forming the silver seed layer comprises forming the silver seed
layer on substantially all surfaces of the plurality of diatom
frustule portions.
469. The method of any one of embodiments 459 to 468, wherein
forming the silver nanostructure comprises forming the silver
nanostructure on a surface within the plurality of perforations to
form a plurality of silver nanostructure plated perforations.
470. The method of any one of embodiments 459 to 469, wherein
forming the silver nanostructure comprises forming the silver
nanostructure on substantially all surfaces of the plurality of
diatom frustule portions.
471. The method of any one of embodiments 457 to 470, wherein
curing the mixture comprises exposing the mixture to an ultraviolet
light having a wavelength shorter than a dimension of the plurality
of perforations.
472. The method of any one of embodiments 469 to 471, wherein
curing the mixture comprises exposing the mixture to an ultraviolet
light having a wavelength shorter than a dimension of at least one
of the plurality of silver seed plated perforations and the
plurality of silver nano structure plated perforations.
473. The method of any one of embodiments 457 to 472, wherein
curing the mixture comprises thermally curing the mixture.
474. The method of any one of embodiments 457 to 473, wherein the
ultraviolet light sensitive component is sensitive to an optical
radiation having a wavelength shorter than a dimension of the
plurality of perforations.
475. The method of any one of embodiments 469 to 474, wherein the
ultraviolet light sensitive component is sensitive to an optical
radiation having a wavelength shorter than a dimension of at least
one of the plurality of silver seed plated perforations and the
plurality of silver nanostructure plated perforations.
476. The method of any one of embodiments 460 to 475, wherein
combining the plurality of diatom frustule portions with the
ultraviolet light sensitive component comprises combining the
plurality of diatom frustule portions with a photoinitiation
synergist agent.
477. The method of embodiment 476, wherein the photoinitiation
synergist agent comprises at least one of an ethoxylated hexanediol
acrylate, a propoxylated hexanediol acrylate, an ethoxylated
trimethylpropane triacrylate, a triallyl cyanurate and an acrylated
amine.
478. The method of any one of embodiments 460 to 477, wherein
combining the plurality of diatom frustule portions with the
ultraviolet light sensitive component comprises combining the
plurality of diatom frustule portions with a photoinitiator
agent.
479. The method of embodiment 478, wherein the photoinitiator agent
comprises at least one of a
2-methyl-1-(4-methylthio)phenyl-2-morpholinyl-1-propanon and an
isopropyl thioxothanone.
480. The method of any one of embodiments 460 to 479, wherein
combining the plurality of diatom frustule portions with the
ultraviolet light sensitive component comprises combining the
plurality of diatom frustule portions with a polar vinyl
monomer.
481. The method of embodiment 480, wherein the polar vinyl monomer
comprises at least one of a n-vinyl-pyrrolidone and a
n-vinylcaprolactam.
482. The method of any one of embodiments 457 to 481, further
comprising combining the plurality of diatom frustule portions with
a rheology modifying agent.
483. The method of any one of embodiments 457 to 482, further
comprising combining the plurality of diatom frustule portions with
a crosslinking agent.
484. The method of any one of embodiments 457 to 483, further
comprising combining the plurality of diatom frustule portions with
a flow and level agent.
485. The method of any one of embodiments 457 to 484, further
comprising combining the plurality of diatom frustule portions with
at least one of an adhesion promoting agent, a wetting agent, and a
viscosity reducing agent.
486. The method of any one of embodiments 457 to 485, wherein the
silver nanostructure comprises at least one of a coating, a
nanowire, a nanoplate, a dense array of nanoparticles, a nanobelt,
and a nanodisk.
487. The method of any one of embodiment 458 to 486, wherein
forming the silver seed layer comprises applying a cyclic heating
regimen to a first silver contributing component and the plurality
of diatom frustule portions.
488. The method of any one of embodiments 458 to 487, wherein
forming the silver seed layer comprises combining the diatom
frustule portion with a seed layer solution.
489. The method of embodiment 488, wherein the seed layer solution
comprises the first silver contributing component and a seed layer
reducing agent.
490. The method of any one of embodiments 459 to 489, wherein
forming the silver nanostructure comprises combining the diatom
frustule portion with a nanostructure forming reducing agent.
491. The method of embodiment 490, wherein forming the silver
nanostructure further comprises heating the diatom frustule portion
after combining the diatom frustule portion with the nanostructure
forming reducing agent.
492. The method of any one of embodiments 459 to 491, wherein
forming the silver nanostructure further comprises titrating the
diatom frustule portion with a titration solution comprising a
nanostructure forming solvent and a second silver contributing
component.
493. The method of any one of embodiments 457 to 492, wherein the
plurality of diatom frustule portions are obtained through a diatom
frustule portion separation process.
494. The method of embodiment 493, wherein the process comprises at
least one of using a surfactant to reduce an agglomeration of a
plurality of diatom frustule portions and using a disc stack
centrifuge.
495. A conductive silver film comprising: a plurality of diatom
frustule portions having a silver nanostructure on a surface of
each of the plurality of diatom frustule portions, the surface
comprising a plurality of perforations.
496. The conductive silver film of embodiment 495, wherein the
plurality of diatom frustule portions comprises a plurality of
broken diatom frustule portion.
497. The conductive silver film of embodiment 495 or 496, wherein
the plurality of diatom frustule portions comprises a plurality of
diatom frustule flakes.
498. The conductive silver film of any one of embodiments 495 to
497, wherein at least one of the plurality of perforations
comprises a diameter of about 250 nanometers to about 350
nanometers.
499. The conductive silver film of any one of embodiments 495 to
498, wherein the silver nanostructure comprises a thickness of
about 10 nanometers to about 500 nanometers.
500. The conductive silver film of any one of embodiments 495 to
499, wherein at least one of the plurality of perforations
comprises a surface having a silver nanostructure.
501. The conductive silver film of any one of embodiments 495 to
500, wherein at least one of the plurality of perforations
comprises a surface having a silver seed layer.
502. The conductive silver film of any one of embodiments 495 to
501, wherein substantially all surfaces of the plurality of diatom
frustule portions comprises a silver nanostructure.
503. The conductive silver film of any one of embodiments 495 to
502, wherein the silver nanostructure comprises at least one of a
coating, a nanowire, a nanoplate, a dense array of nanoparticles, a
nanobelt, and a nanodisk.
504. The conductive silver film of any one of embodiments 495 to
503, further comprising a binder resin.
505. A printed energy storage device comprising: a first electrode;
a second electrode; and a separator between the first electrode and
the second electrode, at least one of the first electrode and the
second electrode including a plurality of frustules comprising
manganese-containing nanostructures.
506. The device of embodiment 505, wherein the frustules have a
substantially uniform property, the substantially uniform property
including at least one of a frustule shape, a frustule dimension, a
frustule porosity, a frustule mechanical strength, a frustule
material, and a degree of brokenness of a frustule.
507. The device of embodiment 505 or 506, wherein the
manganese-containing nanostructures comprise an oxide of
manganese.
508. The device of embodiment 507, wherein the oxide of manganese
comprises manganese(II,III) oxide.
509. The device of embodiment 507 or 508, wherein the oxide of
manganese comprises manganese oxyhydroxide.
510. The device of any one of embodiments 505-509, wherein at least
one of the first electrode and the second electrode comprises
frustules comprising zinc-oxide nano structures.
511. The device of embodiment 510, wherein the zinc-oxide
nanostructures comprise at least one of a nano-wire and a
nano-plate.
512. The device of any one of embodiments 505-511, wherein the
manganese-containing nanostructures cover substantially all
surfaces of the frustules.
513. A membrane of an energy storage device, the membrane
comprising frustules comprising manganese-containing
nanostructures.
514. The membrane of embodiment 513, wherein the
manganese-containing nanostructures comprise an oxide of
manganese.
515. The membrane of embodiment 514, wherein the oxide of manganese
comprises manganese(II,III) oxide.
516. The membrane of embodiment 514 or 515, wherein the oxide of
manganese comprises manganese oxyhydroxide.
517. The membrane of any one of embodiments 513-516, wherein at
least some of the manganese-containing nanostructures comprise a
nano-fiber.
518. The membrane of any one of embodiments 513-517, wherein at
least some of the manganese-containing nanostructures have a
tetrahedral shape.
519. The membrane of any one of embodiments 513-518, wherein the
energy storage device comprises a zinc-manganese battery.
520. An ink for a printed film, the ink comprising: a solution; and
frustules comprising manganese-containing nanostructures dispersed
in the solution.
521. The ink of embodiment 520, wherein the manganese-containing
nanostructures comprise an oxide of manganese.
522. The ink of embodiment 520 or 521, wherein the
manganese-containing nanostructures comprises at least one of
MnO.sub.2, MnO, Mn.sub.2O.sub.3, MnOOH, and Mn.sub.3O.sub.4.
523. The ink of any one of embodiments 520-522, wherein at least
some of the manganese-containing nanostructures comprise a
nano-fiber.
524. The ink of any one of embodiments 520-523, wherein at least
some of the manganese-containing nanostructures have a tetrahedral
shape.
525. A method of forming manganese-containing nanostructures on a
diatom frustule portion, the method comprising: adding the
frustules to an oxygenated manganese acetate solution; and heating
the frustules and the oxygenated manganese acetate solution.
526. The method of embodiment 525, further comprising forming the
oxygenated manganese acetate solution, wherein forming oxygenated
manganese acetate solution comprises dissolving manganese(II)
acetate in oxygenated water.
527. The method of embodiment 526, wherein concentration of the
manganese(II) acetate in the oxygenated manganese acetate solution
is between about 0.05 M and about 1.2 M.
528. The method of any one of embodiments 525-527, further
comprising forming the oxygenated manganese acetate solution,
wherein forming oxygenated manganese acetate solution comprises
dissolving a manganese salt in oxygenated water.
529. The method of embodiment 528, further comprising adding an
oxidizing agent to the oxygenated manganese acetate solution.
530. The method of embodiment 529, wherein the oxidizing agent
comprises peroxide.
531. The method of any one of embodiments 526-530, further
comprising forming the oxygenated water, wherein forming oxygenated
water comprises bubbling oxygen gas into water.
532. The method of embodiment 531, wherein bubbling the oxygen gas
into the water so for a duration of about 10 minutes to about 60
minutes.
533. The method of any one of embodiments 525-532, wherein a weight
percentage of the frustules in the oxygenated manganese acetate
solution is between about 0.01 wt % and about 1 wt %.
534. The method of any one of embodiments 525-533, further
comprising thermally treating the frustules and the oxygenated
manganese acetate solution.
535. The method of embodiment 534, wherein thermally treating the
frustules and the oxygenated manganese acetate solution comprises
using a thermal technique.
536. The method of embodiment 535, wherein using the thermal
technique comprises maintaining the frustules and the oxygenated
manganese acetate solution at a temperature for between about 15
hours and about 40 hours.
537. The method of embodiment 536, wherein the temperature is
between about 50.degree. C. and about 90.degree. C.
538. The method of embodiment 535, wherein using the thermal
technique comprises maintaining the frustules and the oxygenated
manganese acetate solution at a temperature between about
50.degree. C. and about 90.degree. C.
539. The method of any one of embodiments 534-538, wherein
thermally treating the frustules and the oxygenated manganese
acetate solution comprises using a microwave technique.
540. The method of embodiment 539, wherein using the thermal
technique comprises maintaining the frustules and the oxygenated
manganese acetate solution at a temperature for between about 10
minutes and about 120 minutes.
541. The method of embodiment 540, wherein the temperature is
between about 50.degree. C. and about 150.degree. C.
542. The method of embodiment 539, wherein using the thermal
technique comprises maintaining the frustules and the oxygenated
manganese acetate solution at a temperature between about
50.degree. C. and about 150.degree. C.
543. The method of any one of embodiments 525-542, wherein
carbon-containing nanostructures cover some surfaces of the
frustules.
544. The method of embodiment 543, wherein the carbon-containing
nanostructures comprise carbon nanotubes.
545. The method of embodiment 543 or 544, wherein the
carbon-containing nanostructures comprise carbon nano-onions.
546. The method of any one of embodiments 543-545, wherein the
carbon-containing nanostructures comprise reduced graphene
oxide.
547. The device of any one of embodiments 505-512, wherein the
manganese-containing nanostructures cover some surfaces of the
frustules and carbon-containing nanostructures cover other surfaces
of the frustules, the manganese-containing nanostructures
interspersed with the carbon-containing nanostructures.
548. The device of embodiment 547, wherein the carbon-containing
nanostructures comprise carbon nanotubes.
549. The device of embodiment 547 or 548, wherein the
carbon-containing nanostructures comprise carbon nano-onions.
550. The device of any one of embodiments 547-549, wherein the
carbon-containing nanostructures comprise reduced graphene
oxide.
551. The membrane of any one of embodiments 513-519, wherein the
manganese-containing nanostructures cover some surfaces of the
frustules and carbon-containing nanostructures cover other surfaces
of the frustules, the manganese-containing nanostructures
interspersed with the carbon-containing nanostructures.
552. The membrane of embodiment 551, wherein the carbon-containing
nanostructures comprise carbon nanotubes.
553. The membrane of embodiment 551 or 552, wherein the
carbon-containing nanostructures comprise carbon nano-onions.
554. The membrane of any one of embodiments 551-554, wherein the
carbon-containing nanostructures comprise reduced graphene
oxide.
555. The ink of any one of embodiments 520-524, wherein the
manganese-containing nanostructures cover some surfaces of the
frustules and carbon-containing nanostructures cover other surfaces
of the frustules, the manganese-containing nanostructures
interspersed with the carbon-containing nanostructures
556. The ink of embodiment 555, wherein the carbon-containing
nanostructures comprise carbon nanotubes.
557. The ink of embodiment 555 or 556, wherein the
carbon-containing nanostructures comprise carbon nano-onions.
558. The ink of any one of embodiments 555-557, wherein the
carbon-containing nanostructures comprise reduced graphene
oxide.
559. An energy storage device, comprising: a cathode comprising a
first plurality of frustules, wherein the first plurality of
frustules comprises nanostructures comprising an oxide of
manganese; and an anode comprising a second plurality of frustules,
wherein the second plurality of frustules comprises nanostructures
comprising zinc oxide.
560. The energy storage device of embodiment 559, wherein the oxide
of manganese comprises MnO.
561. The energy storage device of embodiment 559 or 560, wherein
the oxide of manganese comprises Mn.sub.3O.sub.4.
562. The energy storage device of any one of embodiments 559 to
561, wherein the oxide of manganese comprises at least one of
Mn.sub.2O.sub.3, and MnOOH.
563. The energy storage device of any one of embodiments 559 to
562, wherein at least one of the first plurality of frustules
comprises about 5 weight % to about 95 weight % of the oxide of
manganese.
564. The energy storage device of embodiment 563, wherein the at
least one of the first plurality of frustules comprises about 75
weight % to about 95 weight % of the oxide of manganese.
565. The energy storage device of any one of embodiments 559 to
564, wherein at least one of the second plurality of frustules
comprises about 5 weight % to about 95 weight % of the zinc
oxide.
566. The energy storage device of embodiment 565, wherein the at
least one of the second plurality of frustules comprises about 50
weight % to about 60 weight % of the zinc oxide.
567. The energy storage device of any one of embodiments 559 to
566, wherein the anode further comprises an electrolyte salt.
568. The energy storage device of embodiment 567, wherein the
electrolyte salt comprises a zinc salt.
569. The energy storage device of any one of embodiments 559 to
568, wherein at least one of the cathode and the anode further
comprises carbon nanotubes.
570. The energy storage device of any one of embodiments 559 to
569, wherein at least one of the cathode and the anode further
comprises a conductive filler.
571. The energy storage device of embodiment 570, wherein the
conductive filler comprises graphite.
572. The energy storage device of any one of embodiments 559 to
571, wherein at least one of the cathode and the anode further
comprises an ionic liquid.
573. The energy storage device of any one of embodiments 559 to
572, wherein at least one of the cathode and the anode further
comprises a binder.
574. The energy storage device of any one of embodiments 559 to
573, further comprising a separator between the cathode and the
anode.
575. The energy storage device of embodiment 574, wherein the
separator further comprises a third plurality of frustules.
576. The energy storage device of embodiment 575, wherein the third
plurality of frustules comprises substantially no surface
modifications.
577. The energy storage device of any one of embodiments 574 to
576, wherein the separator further comprises an electrolyte.
578. The energy storage device of embodiment 577, wherein the
electrolyte comprises the ionic liquid.
579. The energy storage device of embodiment 577 or 578, wherein
the electrolyte comprises the electrolyte salt.
580. The energy storage device of any one of embodiments 574 to
579, wherein the separator further comprises a polymer.
581. The energy storage device of any one of embodiments 559 to
580, further comprising a first current collector coupled to the
cathode and a second current collector coupled to the anode.
582. The energy storage device of embodiment 581, wherein at least
one of the first current collector and the second current collector
comprises a conductive foil.
583. The energy storage device of embodiment 582, wherein the
conductive foil comprises at least one of aluminum, copper, nickel,
stainless steel, graphite, graphene and carbon nanotubes.
584. The energy storage device of embodiment 582 or 583, wherein at
least one of the first current collector and the second current
collector comprises a printed current collector.
585. The energy storage device of embodiment 584, wherein the
printed current collector comprises at least one of aluminum,
copper, nickel, silver, bismuth, conductive carbon, carbon
nanotubes, graphene and graphite.
586. A frustule comprising a plurality of nanostructures on at
least one surface, wherein the plurality of nanostructures
comprises zinc oxide.
587. The frustule of embodiment 586, wherein the frustule comprises
about 5 weight % to about 95 weight % of the plurality of
nanostructures comprising zinc oxide.
588. The frustule of embodiment 587, wherein the frustule comprises
about 50 weight % to about 60 weight % of the nanostructures
comprising zinc oxide.
589. The frustule of any one of embodiments 586 to 588, wherein the
plurality of nanostructures comprises at least one of nanowires,
nanoplates, dense nanoparticles, nanobelts, and nanodisks.
590. A frustule comprising a plurality of nanostructures on at
least one surface, wherein the plurality of nanostructures
comprises an oxide of manganese.
591. The frustule of embodiment 590, wherein the frustule comprises
about 5 weight % to about 95 weight % of the plurality of
nanostructures comprising the oxide of manganese.
592. The frustule of embodiment 591, wherein the frustule comprises
about 75 weight % to about 95 weight % of the plurality of
nanostructures comprising the oxide of manganese.
593. The frustule of any one of embodiments 590 to 592, wherein the
oxide of manganese comprises MnO.
594. The frustule of any one of embodiments 590 to 593, wherein the
oxide of manganese comprises Mn.sub.3O.sub.4.
595. The frustule of any one of embodiments 590 to 594, wherein the
oxide of manganese comprises at least one of Mn.sub.2O.sub.3 and
MnOOH.
596. The frustule of any one of embodiments 590 to 595, wherein the
plurality of nanostructures comprises at least one of nanowires,
nanoplates, dense nanoparticles, nanobelts, and nanodisks.
597. The frustule of any one of embodiments 590 to 596, wherein the
plurality of nanostructures comprises at least one of nano-fibers
and tetrahedral-shaped nanocrystals.
598. An electrode of an energy storage device, comprising: a
plurality of frustules, wherein each of the plurality of frustules
comprises a plurality of nanostructures formed on at least one
surface.
599. The electrode of embodiment 598, wherein the electrode is an
anode of the energy storage device.
600. The electrode of embodiment 599, wherein the anode further
comprises an electrolyte salt.
601. The electrode of embodiment 600, wherein the electrolyte salt
comprises a zinc salt.
602. The electrode of any one of embodiments 599 to 601, wherein
the plurality of nanostructures comprises zinc oxide.
603. The electrode of any one of embodiments 599 to 602, wherein
the plurality of nanostructures comprises at least one of
nanowires, nanoplates, dense nanoparticles, nanobelts, and
nanodisks.
604. The electrode of any one of embodiments 599 to 603, wherein at
least one of the plurality of frustules comprises about 5 weight %
to about 95 weight % of the plurality of nano structures.
605. The electrode of embodiment 604, wherein the at least one of
the plurality of frustules comprises about 50 weight % to about 60
weight % of the plurality of nano structures.
606. The electrode of embodiment 598, wherein the electrode is a
cathode of the energy storage device.
607. The electrode of embodiment 606, wherein the plurality of
nanostructures comprises an oxide of manganese.
608. The electrode of embodiment 607, wherein the oxide of
manganese comprises MnO.
609. The electrode of embodiment 607 or 608, wherein the oxide of
manganese comprises Mn.sub.3O.sub.4.
610. The electrode of any one of embodiments 607 to 609, wherein
the oxide of manganese comprises at least one of Mn.sub.2O.sub.3
and MnOOH.
611. The electrode of any one of embodiments 606 to 610, wherein
the plurality of nanostructures comprises at least one of
nanowires, nanoplates, dense nanoparticles, nanobelts, and
nanodisks.
612. The electrode of any one of embodiments 606 to 611, wherein
the plurality of nanostructures comprises at least one of
nano-fibers and tetrahedral-shaped nanocrystals.
613. The electrode of any one of embodiments 606 to 611, wherein at
least one of the plurality of frustules comprises about 5 weight %
to about 95 weight % of the plurality of nano structures.
614. The electrode of embodiment 613, wherein the at least one of
the plurality of frustules comprises about 75 weight % to about 95
weight % of the plurality of nano structures.
615. The electrode of any one of embodiments 598 to 614, wherein
the electrode further comprises carbon nanotubes.
616. The electrode of any one of embodiments 598 to 615, wherein
the electrode further comprises a conductive filler.
617. The electrode of embodiment 616, wherein the conductive filler
comprises graphite.
618. The electrode of any one of embodiments 598 to 617, wherein
the electrode further comprises an ionic liquid.
619. The electrode of any one of embodiments 598 to 618, wherein
the electrode further comprises a binder.
620. A method of forming zinc oxide nanostructures on a plurality
of frustules, comprising: providing the plurality of frustules;
forming a seed layer comprising zinc oxide on the plurality of
frustules to provide a plurality of zinc oxide seeded frustules;
and forming nanostructures comprising zinc oxide on the seed layer
of the plurality of zinc oxide seeded frustules.
621. The method of embodiment 620, wherein forming the seed layer
comprises providing a seed layer solution comprising about 2 weight
% to about 5 weight % of the plurality of frustules.
622. The method of embodiment 621, wherein the seed layer solution
comprises about 0.1 weight % to about 0.5 weight % zinc salt.
623. The method of embodiment 622, wherein the zinc salt comprises
Zn(CH.sub.3COO).sub.2.
624. The method of any one of embodiments 621 to 623, wherein the
seed layer solution comprises about 94.5 weight % to about 97.9
weight % of an alcohol.
625. The method of embodiment 624, wherein the alcohol comprises
ethanol.
626. The method of any one of embodiments 621 to 625, further
comprising heating the seed layer solution.
627. The method of embodiment 626, wherein heating the seed layer
solution comprises heating the seed layer solution to a temperature
greater than about 80.degree. C.
628. The method of embodiment 626 or 627, wherein heating the seed
layer solution comprises heating the seed layer solution in a
vacuum oven.
629. The method of embodiment 628, wherein heating the seed layer
solution in a vacuum oven comprises heating at a pressure of about
1 millibar.
630. The method of any one of embodiments 621 to 629, further
comprising annealing the plurality of frustules.
631. The method of embodiment 631, wherein annealing comprises
annealing at a temperature of about 200.degree. C. to about
500.degree. C.
632. The method of any one of embodiments 620 to 631, wherein
forming the zinc oxide nanostructures comprises forming a
nanostructure solution comprising about 1 weight % to about 5
weight % of the plurality of zinc oxide seeded frustules.
633. The method of embodiment 632, wherein the nanostructure
solution comprises about 6 weight % to about 10 weight % of a zinc
salt.
634. The method of embodiment 633, wherein the zinc salt comprises
Zn(NO.sub.3).sub.2.
635. The method of any one of embodiments 632 to 634, wherein the
nanostructure solution comprises about 1 weight % to about 2 weight
% of a base.
636. The method of embodiment 635, wherein the base comprises
ammonium hydroxide (NH.sub.4OH).
637. The method of any one of embodiments 632 to 636, wherein the
nanostructure solution comprises about 1 weight % to about 5 weight
% of an additive.
638. The method of embodiment 637, wherein the additive comprises
hexamethylenetetramine (HMTA).
639. The method of any one of embodiments 632 to 638, wherein the
nanostructure solution comprises about 78 weight % to about 91
weight % purified water.
640. The method of any one of embodiments 632 to 638, wherein
forming the zinc oxide nanostructures comprises heating the
nanostructure solution.
641. The method of embodiment 640, wherein heating comprises
heating with a microwave.
642. The method of embodiment 640 or 641, wherein heating comprises
heating to a temperature of about 100.degree. C. to about
250.degree. C.
643. The method of any one of embodiments 640 to 642, further
comprising stirring during heating.
644. The method of any one of embodiments 620 to 643, wherein at
least one of the plurality of frustules comprises about 5 weight %
to about 95 weight % of the zinc oxide.
645. A method of forming nanostructures comprising an oxide of
manganese on a plurality of frustules, comprising: providing the
plurality of frustules; and forming the nanostructures comprising
the oxide of manganese on the plurality of frustules, wherein
forming the nanostructures comprises providing a solution
comprising a manganese source for forming the nanostructures
comprising the oxide of manganese.
646. The method of embodiment 645, wherein the manganese source
comprises a manganese salt, and wherein the solution comprises
about 7 weight % to about 10 weight % of the manganese salt.
647. The method of embodiment 646, wherein the manganese salt
comprises manganese acetate (Mn(CH.sub.3COO).sub.2).
648. The method of any one of embodiments 645 to 647, wherein the
solution comprises about 0.5 weight % to about 2 weight % of the
plurality of frustules.
649. The method of any one of embodiments 645 to 648, wherein the
solution comprises about 5 weight % to about 10 weight % of a
base.
650. The method of embodiment 649, wherein the base comprises
ammonium hydroxide (NH.sub.4OH).
651. The method of any one of embodiments 645 to 650, wherein the
solution comprises about 78 weight % to about 87.5 weight % of
oxygenated purified water.
652. The method of any one of embodiments 645 to 651, further
comprising heating the solution.
653. The method of embodiment 652, wherein heating comprises
heating with microwave.
654. The method of embodiment 652 or 653, wherein heating the
solution comprises heating to a temperature of about 100.degree. C.
to about 250.degree. C.
655. The method of any one of embodiments 652 to 654, further
comprising stirring while heating.
656. An ink for an electrode of an energy storage device,
comprising: a plurality of frustules, wherein each of the plurality
of frustules comprises a plurality of nanostructures formed on a
surface; and a polymer binder.
657. The ink of embodiment 656, wherein the electrode is an anode
of the energy storage device.
658. The ink of embodiment 657, wherein the plurality of
nanostructures comprises zinc oxide.
659. The ink of embodiment 657 or 658, wherein at least one of the
plurality of frustules comprises about 5 weight % to about 95
weight % of the nanostructures.
660. The ink of any one of embodiments 657 to 659, further
comprising an electrolyte salt.
661. The ink of embodiment 660, wherein the electrolyte salt
comprises a zinc salt.
662. The ink of embodiment 661, wherein the zinc salt comprises
zinc tetrafluoroborate.
663. The ink of embodiment 656, wherein the electrode is a cathode
of the energy storage device.
664. The ink of embodiment 663, wherein the plurality of
nanostructures comprises an oxide of manganese.
665. The ink of embodiment 664, wherein the oxide of manganese
comprises MnO.
666. The ink of embodiment 664 or 665, wherein the oxide of
manganese comprises Mn.sub.3O.sub.4.
667. The ink of any one of embodiments 663 to 666, wherein the
oxide of manganese comprises at least one of Mn.sub.2O.sub.3 and
MnOOH.
668. The ink of any one of embodiments 663 to 667, wherein at least
one of the plurality of frustules comprises about 5 weight % to
about 95 weight % of the nanostructures.
669. The ink of any one of embodiments of 656 to 668, further
comprising about 10 weight % to about 20 weight % of the plurality
of frustules.
670. The ink of any one of embodiments 656 to 669, further
comprising an ionic liquid.
671. The ink of embodiment 670, wherein the ink comprises about 2
weight % to about 15 weight % of the ionic liquid.
672. The ink of embodiment 670 or 671, wherein the ionic liquid
comprises 1-ethyl-3-ethylimidazolium tetrafluoroborate.
673. The ink of any one of embodiments of 656 to 672, further
comprising a conductive filler.
674. The ink of embodiment 673, further comprising up to about 10
weight % of the conductive filler.
675. The ink of embodiment 673 or 674, wherein the conductive
filler comprises graphite.
676. The ink of any one of embodiments of 656 to 675, further
comprising carbon nanotubes.
677. The ink of embodiment 676, further comprising about 0.2 weight
% to about 20 weight % of the carbon nanotubes.
678. The ink of embodiment 676 or 677, wherein the carbon nanotubes
comprises multi-wall carbon nanotubes.
679. The ink of any one of embodiments of 656 to 678, wherein the
ink comprises about 1 weight % to about 5 weight % of the polymer
binder.
680. The ink of embodiment 679, wherein the polymer binder
comprises polyvinylidene fluoride.
681. The ink of any one of embodiments of 656 to 680, further
comprising a solvent.
682. The ink of embodiment 681, wherein the ink comprises about 47
weight % to about 86.8 weight % of the solvent.
683. The ink of embodiment 681 or 682, wherein the solvent
comprises N-Methyl-2-pyrrolidone.
684. A method of preparing an ink for an electrode of an energy
storage device, the method comprising: providing an ionic liquid;
dispersing a plurality of carbon nanotubes in the ionic liquid to
form a first dispersion comprising the plurality of carbon
nanotubes and the ionic liquid; and adding a plurality of
frustules, wherein each of the plurality of frustules comprises a
plurality of nanostructures on a surface.
685. The method of embodiment 684, wherein the plurality of
nanostructures comprises zinc oxide.
686. The method of embodiment 684, wherein the plurality of
nanostructures comprises an oxide of manganese.
687. The method of embodiment 686, wherein the oxide of manganese
comprises MnO.
688. The method of embodiment 686 or 687, wherein the oxide of
manganese comprises Mn.sub.3O.sub.4.
689. The method of any one of embodiments 686 to 688, wherein the
oxide of manganese comprises at least one of Mn.sub.2O.sub.3 and
MnOOH.
690. The method of any one of embodiments 684 to 689, further
comprising forming a second dispersion comprising the plurality of
carbon nanotubes, the ionic liquid and a solvent.
691. The method of embodiment 690, wherein the solvent comprises
N-Methyl-2-pyrrolidone.
692. The method of embodiment 690 or 691, wherein adding the
plurality of frustules comprises adding the plurality of frustules
to the second dispersion to form a first mixture.
693. The method of embodiment 692, further comprising adding a
conductive filler to the second dispersion to form the first
mixture.
694. The method of embodiment 693, wherein the conductive filler
comprises graphite.
695. The method of embodiment 692 or 693, further comprising adding
an electrolyte salt to the first mixture to form a second
mixture.
696. The method of embodiment 695, wherein the electrolyte salt
comprises a zinc salt.
697. The method of embodiment 696, wherein the zinc salt comprises
zinc tetrafluoroborate.
698. The method of any one of embodiments 695 to 697, wherein at
least one of adding the plurality of frustules, the conductive
filler and the electrolyte salt comprises stirring.
699. The method of embodiment 698, wherein stirring comprises
applying a centrifugal mixer.
700. The method of any one of embodiments 695 to 699, further
comprising adding a solution to the second mixture to form a third
mixture, wherein the solution comprises the solvent and a polymer
binder.
701. The method of embodiment 700, wherein the polymer binder is
about 10 weight % to about 20 weight % of the solution.
702. The method of embodiment 700 or 701, wherein the polymer
binder comprises polyvinylidene fluoride.
703. The method of any one of embodiments 700 to 702, further
comprising heating the third mixture.
704. The method of embodiment 703, wherein the heating comprises
heating to a temperature of about 80.degree. C. to about
180.degree. C.
705. The method of embodiment 703 or 704, further comprising
stirring during the heating.
706. A method of printing an energy storage device, comprising:
printing a first electrode comprising a first plurality of
frustules, wherein each of the plurality of frustules comprises a
first plurality of nanostructures on a surface; and printing a
separator over the first electrode.
707. The method of embodiment 706, further comprising providing a
first current collector, and wherein printing the first electrode
comprises printing the first electrode over the first current
collector.
708. The method of embodiment 707, wherein providing the first
current collector comprises providing a first conductive foil.
709. The method of any one of embodiments 706 to 708, further
comprising providing a second current collector.
710. The method of embodiment 709, wherein providing the second
current collector comprises providing a second conductive foil.
711. The method of embodiment 710, further comprising printing a
second electrode, wherein the second electrode comprises a second
plurality of frustules, wherein each of the second plurality of
frustules comprises a second plurality of nanostructures on a
surface.
712. The method of embodiment 711, wherein printing the second
electrode comprises printing the second electrode over the
separator.
713. The method of embodiment 711, wherein printing the second
electrode comprises printing the second electrode over the second
current collector.
714. The method embodiment 713, further comprising printing the
separator over the second electrode.
715. The method of embodiment 707, wherein providing the first
current collector comprises printing the first current
collector.
716. The method of embodiment 715, further comprising printing a
second electrode over the separator, wherein the second electrode
comprises a second plurality of frustules, wherein each of the
second plurality of frustules comprises a second plurality of
nanostructures on a surface.
717. The method of embodiment 716, further comprising printing a
second current collector over the second electrode.
718. The method of embodiment 715, wherein further comprising
printing a second current collector at a lateral distance from the
first current collector.
719. The method of embodiment 718, further comprising printing a
second electrode over the second current collector at the lateral
distance from the first current collector, wherein the second
electrode comprises a second plurality of frustules, wherein each
of the second plurality of frustules comprises a second plurality
of nanostructures on a surface.
720. The method of embodiment 719, wherein printing the separator
comprises printing the separator over the first electrode and the
second electrode.
721. A method of fabricating an energy storage device, comprising:
forming a first structure, wherein forming the first structure
comprises: printing a first electrode over a first current
collector, and printing a separator over the first electrode;
forming a second structure, wherein forming the second structure
comprises: printing a second electrode over a second current
collector; and coupling the first structure to the second structure
to form the energy storage device, wherein coupling comprises
providing the separator between the first electrode and the second
electrode.
722. A method of fabricating an energy storage device, comprising:
forming a first structure, wherein forming the first structure
comprises: printing a first electrode over a first current
collector, and printing a first portion of a separator over the
first electrode; forming a second structure, wherein forming the
second structure comprises: printing a second electrode over a
second current collector, and printing a second portion of the
separator over the second electrode; and coupling the first
structure to the second structure to form the energy storage
device, wherein coupling comprises providing the first portion of
the separator and the second portion of the separator between the
first electrode and the second electrode.
723. A method of fabricating an energy storage device, comprising:
forming a first structure, wherein forming the first structure
comprises: printing a first electrode over a first current
collector, printing a separator over the first electrode, and
printing a second electrode on the separator; forming a second
structure, wherein forming the second structure comprises providing
a second current collector; and coupling the first structure to the
second structure to form the energy storage device, wherein
coupling comprises providing the second electrode between the
second current collector and the separator.
724. The method of any one of Embodiments 721-723, wherein the
first current collector comprises a conductive foil.
725. The method of any one of Embodiments 721-723, further
comprising forming the first current collector on a substrate.
726. The method of Embodiment 725, wherein forming the first
current collector comprises printing the first current collector
over the substrate.
727. The method of any one of Embodiments 721-726, wherein the
second current collector comprises a conductive foil.
728. The method of any one of Embodiments 721-726, further
comprising forming the second current collector on a second
substrate.
729. The method of Embodiment 728, wherein forming the first
current collector comprises printing the first current collector
over the second substrate.
730. A method of fabricating an energy storage device, comprising:
printing a first current collector; printing a first electrode over
the first current collector; printing a separator over the first
electrode; printing a second electrode over the separator; and
printing a second current collector over the second electrode.
731. A method of fabricating an energy storage device, comprising:
printing a first current collector; printing a second current
collector at a lateral distance from the first current collector;
printing a first electrode over the first current collector;
printing a second electrode over the second current collector; and
printing a separator over the first electrode and the second
electrode and between the first electrode and the second
electrode.
732. The method of any one of embodiments 721 to 731, wherein the
first electrode comprises a first plurality of frustules, wherein
each of the first plurality of frustules comprises nanostructures
formed on at least one surface.
733. The method of embodiment 732, wherein the nanostructures
comprise an oxide of manganese
734. The method of embodiment 733, wherein the oxide of manganese
comprises MnO.
735. The method of embodiment 733 or 734, wherein the oxide of
manganese comprises Mn.sub.3O.sub.4.
736. The method of any one of embodiments 733 to 735, wherein the
oxide of manganese comprises at least one of Mn.sub.2O.sub.3 and
MnOOH.
737. The method of any one of embodiments 721 to 736, wherein the
second electrode comprises a second plurality of frustules, wherein
each of the second plurality of frustules comprises
nanostructures.
738. The method of embodiment 737, wherein the nanostructures
comprise zinc oxide.
739. The method of any one of embodiments 721 to 738, wherein the
separator comprises a third plurality of frustules, wherein each of
the third plurality of frustules comprises substantially no surface
modifications.
740. An energy storage device comprising: a cathode comprising a
first plurality of frustules, the first plurality of frustules
comprises nanostructures comprising an oxide of manganese; and an
anode comprising a second plurality of frustules, the second
plurality of frustules comprises nanostructures comprising zinc
oxide.
741. The energy storage device of embodiment 740, wherein the oxide
of manganese comprises MnO.
742. The energy storage device of embodiment 740 or 741, wherein
the oxide of manganese comprises at least one of Mn.sub.3O.sub.4,
Mn.sub.2O.sub.3, and MnOOH.
743. The energy storage device of any one of embodiments 740 to
742, wherein at least one of the first plurality of frustules
comprises a ratio of a mass of the oxide of manganese to a mass of
the at least one frustule of about 1:20 to about 20:1.
744. The energy storage device of any one of embodiments 740 to
743, wherein at least one of the second plurality of frustules
comprises a ratio of a mass of the zinc oxide to a mass of the at
least one frustule of about 1:20 to about 20:1.
745. The energy storage device of any one of embodiments 740 to
744, wherein the anode further comprises an electrolyte salt.
746. The energy storage device of embodiment 745, wherein the
electrolyte salt comprises a zinc salt.
747. The energy storage device of any one of embodiments 740 to
746, wherein at least one of the cathode and the anode further
comprises carbon nanotubes.
748. The energy storage device of any one of embodiments 740 to
747, wherein at least one of the cathode and the anode further
comprises a conductive filler.
749. The energy storage device of embodiment 748, wherein the
conductive filler comprises graphite.
750. The energy storage device of any one of embodiments 740 to
749, further comprising a separator between the cathode and the
anode, wherein the separator comprises a third plurality of
frustules.
751. The energy storage device of embodiment 750, wherein the third
plurality of frustules comprises substantially no surface
modifications.
752. The energy storage device of embodiment 750 or 751, wherein at
least one of the cathode, the anode, and the separator comprises an
ionic liquid.
753. The energy storage device of any one of embodiments 740 to
752, wherein the device is a rechargeable battery.
754. The energy storage device of any one of embodiments 740 to
753, wherein the first plurality of frustules comprises a first
plurality of pores substantially not occluded by the nanostructures
comprising the oxide of manganese, and wherein the second plurality
of frustules comprises a second plurality of pores substantially
not occluded by the nanostructures comprising the zinc oxide.
755. A frustule comprising a plurality of nanostructures on at
least one surface, wherein the plurality of nanostructures
comprises zinc oxide, wherein a ratio of a mass of the plurality of
nanostructures to a mass of the frustule is about 1:1 to about
20:1.
756. The frustule of embodiment 755, wherein the plurality of
nanostructures comprises at least one of nanowires, nanoplates,
dense nanoparticles, nanobelts, and nanodisks.
757. The frustule of embodiment 755 or 756, wherein the frustule
comprises a plurality of pores substantially not occluded by the
plurality of nanostructures.
758. A frustule comprising a plurality of nanostructures on at
least one surface, wherein the plurality of nanostructures
comprises an oxide of manganese, wherein a ratio of a mass of the
plurality of nanostructures to a mass of the frustule is about 1:1
to about 20:1.
759. The frustule of embodiment 758, wherein the oxide of manganese
comprises MnO.
760. The frustule of embodiment 758 or 759, wherein the oxide of
manganese comprises Mn.sub.3O.sub.4.
761. The frustule of any one of embodiments 758 to 760, wherein the
oxide of manganese comprises at least one of Mn.sub.2O.sub.3 and
MnOOH.
762. The frustule of any one of embodiments 758 to 761, wherein the
plurality of nanostructures comprises at least one of nanowires,
nanoplates, dense nanoparticles, nanobelts, and nanodisks.
763. The frustule of any one of embodiments 758 to 762, wherein the
frustule comprises a plurality of pores substantially not occluded
by the plurality of nanostructures.
764. An electrode of an energy storage device, the electrode
comprising: a plurality of frustules, wherein each of the plurality
of frustules comprises a plurality of nanostructures formed on at
least one surface, wherein at least one of the plurality of
frustules comprises a ratio of a mass of the plurality of
nanostructures to a mass of the at least one frustule of 1:20 to
20:1.
765. The electrode of embodiment 764, wherein the electrode is an
anode of the energy storage device.
766. The electrode of embodiment 765, wherein the anode further
comprises an electrolyte salt.
767. The electrode of embodiment 766, wherein the electrolyte salt
comprises a zinc salt.
768. The electrode of any one of embodiments 765 to 767, wherein
the plurality of nanostructures comprises zinc oxide.
769. The electrode of any one of embodiments 764 to 768, wherein
the plurality of nanostructures comprises at least one of
nanowires, nanoplates, dense nanoparticles, nanobelts, and
nanodisks.
770. The electrode of embodiment 764 or 769, wherein the electrode
is a cathode of the energy storage device.
771. The electrode of embodiment 770, wherein the plurality of
nanostructures comprises an oxide of manganese.
772. The electrode of embodiment 771, wherein the oxide of
manganese comprises MnO.
773. The electrode of embodiment 771 or 772, wherein the oxide of
manganese comprises at least one of Mn.sub.3O.sub.4,
Mn.sub.2O.sub.3 and MnOOH.
774. The electrode of any one of embodiments 764 to 773, further
comprising carbon nanotubes.
775. The electrode of any one of embodiments 764 to 774, further
comprising a conductive filler.
776. The electrode of embodiment 775, wherein the conductive filler
comprises graphite.
777. The electrode of any one of embodiments 764 to 776, further
comprising an ionic liquid.
778. The electrode of any one of embodiments 764 to 777, wherein
each of the plurality of frustules comprises a plurality of pores
substantially not occluded by the plurality of nano structures.
779. The energy storage device of any one of embodiments 559 to 562
and 565 to 585, wherein a mass of the nanostructures comprising the
oxide of manganese of at least one frustule of the first plurality
of frustules to a mass of the at least one frustule is about 1:20
to about 100:1.
780. The energy storage device of embodiment 779, wherein the mass
of the nanostructures comprising the oxide of manganese of at least
one frustule of the first plurality of frustules to the mass of the
at least one frustule is about 1:1 to about 100:1.
781. The energy storage device of embodiment 779, wherein the mass
of the nanostructures comprising the oxide of manganese of at least
one frustule of the first plurality of frustules to the mass of the
at least one frustule is about 1:20 to about 100:1.
782. The energy storage device of any one of embodiments 559 to
564, 567 to 585 and 779 to 781, wherein a mass of the ZnO of at
least one frustule of the second plurality of frustules to a mass
of the at least one frustule of the second plurality of frustules
is about 1:20 to about 100:1.
783. The energy storage device embodiment 782, wherein the mass of
the ZnO of at least one frustule of the second plurality of
frustules to the mass of the at least one frustule of the second
plurality of frustules is about 1:1 to about 100:1.
784. The energy storage device embodiment 782, wherein the mass of
the ZnO of at least one frustule of the second plurality of
frustules to the mass of the at least one frustule of the second
plurality of frustules is about 20:1 to about 100:1.
785. The frustule of any one of embodiments 586 and 589, wherein a
mass of the ZnO to a mass of the frustule is about 1:20 to about
100:1.
786. The frustule of embodiment 785, wherein the mass of the ZnO to
the mass of the frustule is about 1:1 to about 100:1.
787. The frustule of embodiment 785, wherein the mass of the ZnO to
the mass of the frustule is about 20:1 to about 100:1.
788. The frustule of any one of embodiments 590 and 593 to 597,
wherein a mass of the plurality of nanostructures comprising the
oxide of manganese to a mass of the frustule is about 1:20 to about
100:1.
789. The frustule of embodiment 788, wherein the mass of the
plurality of nanostructures comprising the oxide of manganese to
the mass of the frustule is about 1:1 to about 100:1.
790. The frustule of embodiment 788, wherein the mass of the
plurality of nanostructures comprising the oxide of manganese to
the mass of the frustule is about 20:1 to about 100:1.
791. The electrode of any one of embodiments 598 to 603 and 606 to
612, 615 to 619, wherein a mass of the plurality of nanostructures
to a mass of at least one frustule of the plurality of frustules is
about 1:20 to about 100:1.
792. The electrode of embodiment 791, wherein the mass of the
plurality of nanostructures to the mass of the at least one
frustule is about 1:1 to about 100:1.
793. The electrode of embodiment 791, wherein the mass of the
plurality of nanostructures to the mass of the at least one
frustule is about 20:1 to about 100:1.
794. The method of any one of embodiments 620 to 643, wherein a
mass of the zinc oxide to a mass of at least one frustule of the
plurality of frustules is about 1:20 to about 100:1.
795. The method of embodiment 794, wherein the mass of the zinc
oxide to the mass of the at least one frustule is about 1:1 to
about 100:1.
796. The method of embodiment 794, wherein the mass of the zinc
oxide to the mass of the at least one frustule is about 20:1 to
about 100:1.
797. The method of any one of embodiments 645 to 655, wherein a
mass of the nanostructures comprising the oxide of manganese to a
mass of at least one frustule of the plurality of frustules is
about 1:20 to about 100:1.
798. The method of embodiment 797, wherein the mass of the
nanostructures comprising the oxide of manganese to the mass of the
at least one frustule is about 1:1 to about 100:1.
799. The method of embodiment 797, wherein the mass of the
nanostructures comprising the oxide of manganese to the mass of the
at least one frustule is about 20:1 to about 100:1.
800. The ink of any one of embodiments 656 to 658, 660 to 667 and
669 to 683, wherein a mass of the plurality of nanostructures to a
mass of at least one frustule of the plurality of frustules is
about 1:20 to about 100:1.
801. The ink of embodiment 800, wherein the mass of the plurality
of nanostructures to the mass of the at least one frustule is about
1:1 to about 100:1.
802. The ink of embodiment 800, wherein a mass of the plurality of
nanostructures to the mass of the at least one frustule is about
20:1 to about 100:1.
803. A supercapacitor comprising a pair of electrodes and an
electrolyte comprising an ionic liquid, wherein at least one of the
electrodes comprises a plurality of frustules having formed thereon
a surface active material.
804. The super capacitor of embodiment 803, wherein each of the
plurality of frustules is coated with the surface active
material.
805. The supercapacitor of embodiments 803 or 804, wherein a first
one of the electrodes comprises the frustules.
806. The supercapacitor of any one of embodiments 803 to 805,
wherein each of the pair of electrodes comprises the frustules.
807. The supercapacitor of any one of embodiments 803 to 806,
wherein no ion transport occurs from one electrode to the other as
part of an electrochemical reaction during charge or discharge.
808. The supercapacitor of any one of embodiments 803 to 807,
wherein the supercapacitor is configured to be charged to have a
voltage difference between the electrodes that exceeds 2 volts.
809. The supercapacitor of any one of embodiments 803 to 808,
wherein the ionic liquid comprises a molten salt.
810. The supercapacitor of any one of embodiments 803 to 809,
wherein the surface active material comprises nanostructures formed
on surfaces of the frustules.
811. The supercapacitor of any one of embodiments 803 to 810,
wherein the surface active material comprises nanostructures
covering substantially all surfaces of the frustules.
812. The supercapacitor of any one of embodiments 803 to 811,
wherein at least one of the electrodes is configured substantially
as one or both of an electric double layer capacitor and a pseudo
capacitor.
813. The supercapacitor of any one of embodiments 803 to 812,
wherein at least one of the electrodes is configured substantially
as one of an electric double layer capacitor or a pseudo capacitor
while not being configured substantially as the other of the double
layer capacitor or the pseudo capacitor.
814. The supercapacitor of any one of embodiments 803 to 813,
wherein upon application of a voltage across the electrodes, a
first sheet of charge of first polarity forms at surfaces of the
surface active material of the at least one of the electrodes
configured as an electric double layer capacitor, and a second
sheet of charge of second polarity forms adjacent to the at least
one of the electrodes configured as the double layer capacitor,
wherein the first and second sheets of charge are interposed by a
layer of the electrolyte.
815. The supercapacitor of any one of embodiments 803 to 814,
wherein upon application of a voltage across the electrodes, the at
least one of the electrodes configured as a pseudo capacitor stores
energy by a reversible Faradaic redox reaction on the surface of
the surface active material.
816. The supercapacitor of any one of embodiments 803 to 815,
wherein the surface active material of at least one of the
electrodes comprises carbon nanotubes (CNTs).
817. The supercapacitor of embodiment 816, wherein the surface
active material of each of the pair of the electrodes comprises the
CNTs.
818. The supercapacitor of embodiments 816 or 817, wherein the
surface active material comprises the CNTs formed on a surface of
each of the frustules.
819. The supercapacitor of any one of embodiments 816 to 818,
wherein the at least one of the electrodes comprising the CNTs are
configured substantially as an electric double layer capacitor.
820. The supercapacitor of any one of embodiments 803 to 815,
wherein the surface active material of at least one of the
electrodes comprises one or both of a zinc oxide and a manganese
oxide.
821. The supercapacitor of embodiment 820, wherein the surface
active material of the at least one of the electrodes comprises one
or both of zinc oxide nanoparticles and manganese oxide
nanoparticles.
822. The supercapacitor of embodiments 820 or 821, wherein the
surface active material of the at least one of the electrodes
comprises one or both of the zinc oxide nanoparticles and the
manganese oxide nanoparticle formed on a surface of each of the
frustules.
823. The supercapacitor of any one of embodiments 820 to 822,
wherein the surface active material of each of the pair of the
electrodes comprises one or both of the zinc oxide and the
manganese oxide.
824. The supercapacitor of any one of embodiments 820 to 823,
wherein the at least one of the electrodes comprising one or both
of the zinc oxide and the manganese oxide are configured
substantially as a pseudo capacitor.
825. The supercapacitor of any one of embodiments 803 to 815,
wherein the surface active material of at least one of the
electrodes comprises one but not the other of the zinc oxide and
the manganese oxide.
826. The supercapacitor of any one of embodiments 820 to 825,
wherein the manganese oxide comprises one or more of manganese
dioxide (MnO.sub.2), manganese(II, III) oxide (Mn.sub.3O.sub.4),
manganese(II) oxide (MnO), manganese(III) oxide
(Mn.sub.2O.sub.3).
827. The supercapacitor of any one of embodiments 816 to 826,
wherein the surface active material of one of the pair of
electrodes comprises CNTs and the surface active material of the
other of pair of electrodes comprises one or both of the zinc oxide
and the manganese oxide.
828. The supercapacitor of any one of embodiments 803 to 827,
wherein the ionic liquid comprises one or more cations selected
from the group consisting of butyltrimethylammonium,
1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium,
1-methyl-3-propylimidazolium, 1-hexyl-3-methylimidazolium, choline,
ethylammonium, tributylmethylphosphonium,
tributyl(tetradecyl)phosphonium, trihexyl(tetradecyl)phosphonium,
1-ethyl-2,3-methylimidazolium, 1-butyl-1-methylpiperidinium,
diethylmethylsulfonium, 1-methyl-3-propylimidazolium,
1-ethyl-3-methylimidazolium, 1-methyl-1-propylpiperidinium,
1-butyl-2-methylpyridinium, 1-butyl-4-methylpyridinium,
1-butyl-1-methylpyrrolidinium, diethylmethylsulfonium and
combinations thereof.
829. The supercapacitor of any one of embodiments 803 to 828,
wherein the ionic liquid comprises or more anions selected from the
group consisting of tris(pentafluoroethyl)trifluorophosphate,
trifluoromethanesulfonate, hexafluorophosphate, tetrafluoroborate,
ethyl sulfate, dimethyl phosphate, methansulfonate, triflate,
tricyanomethanide, dibutylphosphate,
bis(trifluoromethylsulfonyl)imide, bis-2,4,4-(trimethylpentyl)
phosphinate, iodide, chloride, bromide, nitrate and combinations
thereof.
830. The supercapacitor of any one of embodiments 803 to 829,
wherein the ionic liquid comprises 1-ethyl-3-methylimidazolium
tetrafluoroborate (C.sub.2mimBF.sub.4).
831. The supercapacitor of any one of embodiments 803 to 830,
wherein the electrolyte further comprises a salt dissolved
therein.
832. The supercapacitor of embodiment 831, wherein the salt has at
least a cation that is different from a cation of the ionic
liquid.
833. The supercapacitor of embodiments 831 or 832, wherein the salt
comprises a cation selected from a group consisting of zinc,
sodium, potassium, magnesium, calcium, aluminum, lithium, barium
and combinations thereof.
834. The supercapacitor of any one of embodiments 831 to 833,
wherein the salt comprises at least an anion that is different from
an anion of the ionic liquid.
835. The supercapacitor of any one of embodiments 831 to 834,
wherein the salt comprises an anion selected from the group
consisting of chloride, bromide, fluoride,
bis(trifluoromethanesulfonyl)imide, sulfate, bisulfite, nitrate,
nitrite, carbonate, hydroxide, perchloride, bicarbonate,
tetrafluoroborate, methansulfonate, acetate, phosphate, citrate,
hexafluorophosphate and combinations thereof.
836. The supercapacitor of any one of embodiments 831 to 835,
wherein the salt comprises an organic salt.
837. The supercapacitor of any one of embodiments 831 to 836,
wherein the salt comprises an anion selected from the group
consisting of tetraethylammonium tetrafluoroborate,
tetraethylammonium difluoro(oxalate)borate, methylammonium
tetrafluoroborate, triethylmethylammonium tetrafluoroborate,
tetrafluoroboric acid dimethyldi ethylammonium,
triethylmethylammonium tetrafluoroborate, tetrapropylammonium
tetrafluoroborate, methyltributylammonium tetrafluoroborate,
tetrabutylammonium tetrafluoroborate, tetrahexylammonium
tetrafluoroborate, tetramethylammonium tetrafluoroborate,
tetraethyl phosphonium tetrafluoroborate, tetrapropylphosphonium
tetrafluoroborate, tetrabutylphosphonium, tetrafluoroborate and
combinations thereof.
838. The supercapacitor of any one of embodiments 831 to 836,
wherein the salt comprises an inorganic salt.
839. The supercapacitor of embodiment 838, wherein the inorganic
salt comprises a salt selected from the group consisting of LiCl;
Li.sub.2SO.sub.4, LiClO.sub.4, NaCl, Na.sub.2SO.sub.4, NaNO.sub.3,
KCl, K.sub.2SO.sub.4, KNO.sub.3, Ca(NO.sub.3).sub.2, MgSO.sub.4 and
combinations thereof.
840. The supercapacitor of any one of embodiments 803 to 839,
wherein the electrolyte comprises an acid selected from the group
consisting of H.sub.2SO.sub.4, HCl, HNO.sub.3, HClO.sub.4 and
combinations thereof.
841. The supercapacitor of any one of embodiments 803 to 839,
wherein the electrolyte comprises a base selected from the group
consisting of KOH, NaOH, LiOH, NH.sub.4OH and combinations
thereof.
842. The supercapacitor of any one of embodiments 831 to 833 and
835 to 841, wherein the salt comprises the same anion as an anion
of the ionic liquid.
843. The supercapacitor of embodiment 838, wherein the salt
comprises zinc tetrafluoroborate Zn(BF.sub.4).sub.2.
844. The supercapacitor of any one of embodiments 803 to 843,
further comprising a separator interposed between the pair of
electrodes.
845. The supercapacitor of embodiment 844, wherein the separator
comprises a plurality of frustules.
846. The supercapacitor of embodiment 845, wherein the separator
further comprises graphene oxide.
847. The supercapacitor of any one of embodiments 803 to 846,
wherein the frustules comprise chemically unmodified frustules.
848. A supercapacitor comprising a pair of electrodes contacting an
electrolyte, wherein at least one of the electrodes comprise a
plurality of frustules and a zinc oxide.
849. The supercapacitor of embodiment 848, wherein each of the
frustules is coated with the zinc oxide.
850. The supercapacitor of embodiments 848 or 849, wherein each of
the frustules is coated with nanostructures comprising the zinc
oxide.
851. The supercapacitor of any one of embodiments 848 to 850,
wherein one or both of the electrodes further comprise carbon
nanotubes (CNTs).
852. The supercapacitor of embodiment 848, wherein one of the
electrodes comprises the zinc oxide and the other of the electrodes
comprises carbon nanotubes (CNTs).
853. The supercapacitor of embodiments 851 or 852, wherein each of
the frustules are coated with the CNTs.
854. The supercapacitor of any one of embodiments 848 to 853,
wherein the electrolyte comprises an aqueous electrolyte.
855. The supercapacitor of any one of embodiments 848 to 853,
wherein the electrolyte comprises a non-aqueous electrolyte.
856. The supercapacitor of any one of embodiments 848 to 855,
wherein no ion transport occurs from one electrode to the other as
part of an electrochemical reaction during charge or discharge.
857. The supercapacitor of any one of embodiments 848 to 856,
wherein at least one of the electrodes is configured substantially
as one or both of an electric double layer capacitor and a pseudo
capacitor.
858. The supercapacitor of any one of embodiments 848 to 857,
wherein at least one of the electrodes is configured substantially
as one of an electric double layer capacitor or a pseudo capacitor
while not being configured substantially as the other of the double
layer capacitor or the pseudo capacitor.
859. The supercapacitor of any one of embodiments 848 to 858,
wherein upon application of a voltage across the electrodes, a
first sheet of charge of first polarity forms at surfaces of the
surface active material of the at least one of the electrodes
configured as an electric double layer capacitor, and a second
sheet of charge of second polarity forms adjacent to the at least
one of the electrodes configured as the double layer capacitor,
wherein the first and second sheets of charge are interposed by a
layer of electrolyte.
860. The supercapacitor of any one of embodiments 848 to 859,
wherein upon application of a voltage across the electrodes, the at
least one of the electrodes configured as a pseudo capacitor stores
energy by a reversible Faradaic redox reaction on the surface of
the surface active material.
861. The supercapacitor of any one of embodiments 848 to 860,
wherein the at least one of the electrodes comprising the zinc
oxide are configured substantially as a pseudo capacitor.
862. The supercapacitor of any one of embodiments 848 to 861,
wherein the at least one of the electrodes comprising the CNTs are
configured substantially as an electric double layer capacitor.
863. The supercapacitor of any one of embodiments 848 to 861,
wherein the electrolyte comprises an ionic liquid.
864. The supercapacitor of any one of embodiments 848 to 863,
wherein the ionic liquid comprises one or more cations selected
from the group consisting of butyltrimethylammonium,
1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium,
1-methyl-3-propylimidazolium, 1-hexyl-3-methylimidazolium, choline,
ethylammonium, tributylmethylphosphonium,
tributyl(tetradecyl)phosphonium, trihexyl(tetradecyl)phosphonium,
1-ethyl-2,3-methylimidazolium, 1-butyl-1-methylpiperidinium,
diethylmethylsulfonium, 1-methyl-3-propylimidazolium,
1-ethyl-3-methylimidazolium, 1-methyl-1-propylpiperidinium,
1-butyl-2-methylpyridinium, 1-butyl-4-methylpyridinium,
1-butyl-1-methylpyrrolidinium, diethylmethylsulfonium and
combinations thereof.
865. The supercapacitor of any one of embodiments 848 to 864,
wherein the ionic liquid comprises or more anions selected from the
group consisting of tris(pentafluoroethyl)trifluorophosphate,
trifluoromethanesulfonate, hexafluorophosphate, tetrafluoroborate,
ethyl sulfate, dimethyl phosphate, methansulfonate, triflate,
tricyanomethanide, dibutylphosphate,
bis(trifluoromethylsulfonyl)imide, bis-2,4,4-(trimethylpentyl)
phosphinate, iodide, chloride, bromide, nitrate and combinations
thereof.
866. The supercapacitor of any one of embodiments 848 to 865,
wherein the ionic liquid comprises 1-ethyl-3-methylimidazolium
tetrafluoroborate (C.sub.2mimBF.sub.4).
867. The supercapacitor of any one of embodiments 848 to 866,
wherein the electrolyte further comprises a salt dissolved
therein.
868. The supercapacitor of embodiment 867, wherein the salt has at
least a cation that is different from a cation of the ionic
liquid.
869. The supercapacitor of embodiments 867 or 868, wherein the salt
comprises a cation selected from a group consisting of zinc,
sodium, potassium, magnesium, calcium, aluminum, lithium, barium
and combinations thereof.
870. The supercapacitor of any one of embodiments 867 to 869,
wherein the salt comprises at least an anion that is different from
an anion of the ionic liquid.
871. The supercapacitor of any one of embodiments 867 to 870,
wherein the salt comprises an anion selected from the group
consisting of chloride, bromide, fluoride,
bis(trifluoromethanesulfonyl)imide, sulfate, bisulfite, nitrate,
nitrite, carbonate, hydroxide, perchloride, bicarbonate,
tetrafluoroborate, methansulfonate, acetate, phosphate, citrate,
hexafluorophosphate and combinations thereof.
872. The supercapacitor of any one of embodiments 867 to 871,
wherein the salt comprises an organic salt.
873. The super capacitor of any one of embodiments 867 to 872,
wherein the salt comprises an anion selected from the group
consisting of tetraethylammonium tetrafluoroborate,
tetraethylammonium difluoro(oxalate)borate, methylammonium
tetrafluoroborate, triethylmethylammonium tetrafluoroborate,
tetrafluoroboric acid dimethyldi ethylammonium,
triethylmethylammonium tetrafluoroborate, tetrapropylammonium
tetrafluoroborate, methyltributylammonium tetrafluoroborate,
tetrabutylammonium tetrafluoroborate, tetrahexylammonium
tetrafluoroborate, tetramethylammonium tetrafluoroborate,
tetraethyl phosphonium tetrafluoroborate, tetrapropylphosphonium
tetrafluoroborate, tetrabutylphosphonium, tetrafluoroborate and
combinations thereof.
874. The supercapacitor of any one of embodiments 867 to 871,
wherein the salt comprises an inorganic salt.
875. The supercapacitor of embodiment 874, wherein the inorganic
salt comprises a salt selected from the group consisting of LiCl;
Li.sub.2SO.sub.4, LiClO.sub.4, NaCl, Na.sub.2SO.sub.4, NaNO.sub.3,
KCl, K.sub.2SO.sub.4, KNO.sub.3, Ca(NO.sub.3).sub.2, MgSO.sub.4 and
combinations thereof.
876. The supercapacitor of any one of embodiments 848 to 874,
wherein the electrolyte comprises an acid selected from the group
consisting of H.sub.2SO.sub.4, HCl, HNO.sub.3, HClO.sub.4 and
combinations thereof.
877. The supercapacitor of any one of embodiments 848 to 874,
wherein the electrolyte comprises a base selected from the group
consisting of KOH, NaOH, LiOH, NH.sub.4OH and combinations
thereof.
878. The supercapacitor of any one of embodiments 867 to 869 and
870 to 877, wherein the salt comprises the same anion as an anion
of the ionic liquid.
879. The supercapacitor of embodiment 878, wherein the salt
comprises zinc tetrafluoroborate Zn(BF.sub.4).sub.2.
880. The supercapacitor of any one of embodiments 848 to 879,
further comprising a separator interposed between the pair of
electrodes.
881. The supercapacitor of embodiment 880, wherein the separator
comprises a plurality of frustules.
882. The supercapacitor of embodiment 881, wherein the separator
further comprises graphene oxide.
883. The supercapacitor of any one of embodiments 848 to 882,
wherein the frustules comprise chemically unmodified frustules.
884. A supercapacitor comprising a pair of electrodes contacting a
non-aqueous electrolyte, wherein at least one of the electrodes
comprise a plurality of frustules and a manganese oxide.
885. The supercapacitor of embodiment 884, wherein each of the
frustules are coated with the manganese oxide.
886. The supercapacitor of embodiments 884 or 885, wherein each of
the frustules are coated with nanostructures comprising the
manganese oxide.
887. The supercapacitor of any one of embodiments 884 to 886,
wherein the at least one of the electrodes further comprise zinc
oxide.
888. The supercapacitor of any one of embodiments 884 to 887,
wherein each of the frustules are coated with the zinc oxide.
889. The supercapacitor of any one of embodiments 884 to 888,
wherein each of the frustules are coated with nanostructures
comprising the zinc oxide.
890. The supercapacitor of any one of embodiments 884 to 889,
wherein one or both of the electrodes further comprise carbon
nanotubes (CNTs).
891. The supercapacitor of embodiment 884, wherein one of the
electrodes comprises the manganese oxide and the other of the
electrodes comprises carbon nanotubes (CNTs).
892. The supercapacitor of embodiments 890 or 891, wherein each of
the frustules are coated with the CNTs.
893. The supercapacitor of any one of embodiments 884 to 892,
wherein the manganese oxide comprises one or more of manganese
dioxide (MnO.sub.2), manganese(II, III) oxide (Mn.sub.3O.sub.4),
manganese(II) oxide (MnO), manganese(III) oxide
(Mn.sub.2O.sub.3).
894. The supercapacitor of any one of embodiments 884 to 893,
wherein no ion transport occurs from one electrode to the other as
part of an electrochemical reaction during charge or discharge.
895. The supercapacitor of any one of embodiments 884 to 894,
wherein at least one of the electrodes is configured substantially
as one or both of an electric double layer capacitor and a pseudo
capacitor.
896. The supercapacitor of any one of embodiments 884 to 895,
wherein at least one of the electrodes is configured substantially
as one of an electric double layer capacitor or a pseudo capacitor
while not being configured substantially as the other of the double
layer capacitor or the pseudo capacitor.
897. The supercapacitor of any one of embodiments 884 to 896,
wherein upon application of a voltage across the electrodes, a
first sheet of charge of first polarity forms at surfaces of the
surface active material of the at least one of the electrodes
configured as an electric double layer capacitor, and a second
sheet of charge of second polarity forms adjacent to the at least
one of the electrodes configured as the double layer capacitor,
wherein the first and second sheets of charge are interposed by a
layer of electrolyte.
898. The supercapacitor of any one of embodiments 884 to 897,
wherein upon application of a voltage across the electrodes, the at
least one of the electrodes configured as a pseudo capacitor stores
energy by a reversible Faradaic redox reaction on the surface of
the surface active material.
899. The supercapacitor of any one of embodiments 884 to 899,
wherein the at least one of the electrodes comprising the zinc
oxide are configured substantially as a pseudo capacitor.
900. The supercapacitor of any one of embodiments 890 to 892,
wherein the at least one of the electrodes comprising the CNTs are
configured substantially as an electric double layer capacitor.
901. The supercapacitor of any one of embodiments 884 to 900,
wherein the electrolyte comprises an ionic liquid.
902. The supercapacitor of any one of embodiments 884 to 901,
wherein the ionic liquid comprises one or more cations selected
from the group consisting of butyltrimethylammonium,
1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium,
1-methyl-3-propylimidazolium, 1-hexyl-3-methylimidazolium, choline,
ethylammonium, tributylmethylphosphonium,
tributyl(tetradecyl)phosphonium, trihexyl(tetradecyl)phosphonium,
1-ethyl-2,3-methylimidazolium, 1-butyl-1-methylpiperidinium,
diethylmethylsulfonium, 1-methyl-3-propylimidazolium,
1-ethyl-3-methylimidazolium, 1-methyl-1-propylpiperidinium,
1-butyl-2-methylpyridinium, 1-butyl-4-methylpyridinium,
1-butyl-1-methylpyrrolidinium, diethylmethylsulfonium and
combinations thereof.
903. The supercapacitor of any one of embodiments 884 to 902,
wherein the ionic liquid comprises or more anions selected from the
group consisting of tris(pentafluoroethyl)trifluorophosphate,
trifluoromethanesulfonate, hexafluorophosphate, tetrafluoroborate,
ethyl sulfate, dimethyl phosphate, methansulfonate, triflate,
tricyanomethanide, dibutylphosphate,
bis(trifluoromethylsulfonyl)imide, bis-2,4,4-(trimethylpentyl)
phosphinate, iodide, chloride, bromide, nitrate and combinations
thereof.
904. The supercapacitor of any one of embodiments 884 to 903,
wherein the ionic liquid comprises 1-ethyl-3-methylimidazolium
tetrafluoroborate (C.sub.2mimBF.sub.4).
905. The supercapacitor of any one of embodiments 884 to 904,
wherein the electrolyte further comprises a salt dissolved
therein.
906. The supercapacitor of embodiment 905, wherein the salt has at
least a cation that is different from a cation of the ionic
liquid.
907. The supercapacitor of embodiments 905 or 906, wherein the salt
comprises a cation selected from a group consisting of zinc,
sodium, potassium, magnesium, calcium, aluminum, lithium, barium
and combinations thereof.
908. The supercapacitor of any one of embodiments 905 to 907,
wherein the salt comprises at least an anion that is different from
an anion of the ionic liquid.
909. The supercapacitor of any one of embodiments 905 to 908,
wherein the salt comprises an anion selected from the group
consisting of chloride, bromide, fluoride,
bis(trifluoromethanesulfonyl)imide, sulfate, bisulfite, nitrate,
nitrite, carbonate, hydroxide, perchloride, bicarbonate,
tetrafluoroborate, methansulfonate, acetate, phosphate, citrate,
hexafluorophosphate and combinations thereof.
910. The supercapacitor of any one of embodiments 905 to 909,
wherein the salt comprises an organic salt.
911. The super capacitor of any one of embodiments 905 to 910,
wherein the salt comprises an anion selected from the group
consisting of tetraethylammonium tetrafluoroborate,
tetraethylammonium difluoro(oxalate)borate, methylammonium
tetrafluoroborate, triethylmethylammonium tetrafluoroborate,
tetrafluoroboric acid dimethyldi ethylammonium,
triethylmethylammonium tetrafluoroborate, tetrapropylammonium
tetrafluoroborate, methyltributylammonium tetrafluoroborate,
tetrabutylammonium tetrafluoroborate, tetrahexylammonium
tetrafluoroborate, tetramethylammonium tetrafluoroborate,
tetraethyl phosphonium tetrafluoroborate, tetrapropylphosphonium
tetrafluoroborate, tetrabutylphosphonium, tetrafluoroborate and
combinations thereof.
912. The supercapacitor of any one of embodiments 905 to 909,
wherein the salt comprises an inorganic salt.
913. The supercapacitor of embodiment 912, wherein the inorganic
salt comprises a salt selected from the group consisting of LiCl;
Li.sub.2SO.sub.4, LiClO.sub.4, NaCl, Na.sub.2SO.sub.4, NaNO.sub.3,
KCl, K.sub.2SO.sub.4, KNO.sub.3, Ca(NO.sub.3).sub.2, MgSO.sub.4 and
combinations thereof.
914. The supercapacitor of any one of embodiments 884 to 913,
wherein the electrolyte comprises an acid selected from the group
consisting of H.sub.2SO.sub.4, HCl, HNO.sub.3, HClO.sub.4 and
combinations thereof.
915. The supercapacitor of any one of embodiments 884 to 913,
wherein the electrolyte comprises a base selected from the group
consisting of KOH, NaOH, LiOH, NH.sub.4OH and combinations
thereof.
916. The supercapacitor of any one of embodiments 905 to 907 and
909 to 915, wherein the salt comprises the same anion as an anion
of the ionic liquid.
917. The supercapacitor of embodiment 905, wherein the salt
comprises zinc tetrafluoroborate Zn(BF.sub.4).sub.2.
918. The supercapacitor of any one of embodiments 905 to 917,
further comprising a separator interposed between the pair of
electrodes.
919. The supercapacitor of embodiment 918, wherein the separator
comprises a plurality of frustules.
920. The supercapacitor of embodiment 919, wherein the separator
further comprises graphene oxide.
921. The supercapacitor of any one of embodiments 905 to 921,
wherein the frustules comprise chemically unmodified frustules.
922. A supercapacitor comprising a pair of electrodes contacting an
electrolyte, wherein at least one of the electrodes comprise a
plurality of frustules and carbon nanotubes (CNTs).
923. The supercapacitor of embodiment 922, wherein a surface of
each of the frustules has one or more of the CNTs formed
thereon.
924. The supercapacitor of embodiments 922 or 923, wherein at least
one of the electrodes further comprise at least one of zinc oxide
and manganese oxide.
925. The supercapacitor of any one of embodiments 922 to 924,
wherein the surface of each of the frustules has one or more of the
at least one of the zinc oxide and the manganese oxide formed
thereon.
926. The supercapacitor of any one of embodiments 922 to 925,
wherein the surface of each of the frustules has formed thereon
nanostructures comprising the at least one of the zinc oxide and
the manganese oxide.
927. The supercapacitor of any one of embodiments 924 to 926,
wherein the manganese oxide comprises one or more of manganese
dioxide (MnO.sub.2), manganese(II, III) oxide (Mn.sub.3O.sub.4),
manganese(II) oxide (MnO), manganese(III) oxide
(Mn.sub.2O.sub.3).
928. The supercapacitor of any one of embodiments 922 to 927,
wherein no ion transport occurs from one electrode to the other as
part of an electrochemical reaction during charge or discharge.
929. The supercapacitor of any one of embodiments 922 to 928,
wherein at least one of the electrodes is configured substantially
as one or both of an electric double layer capacitor and a pseudo
capacitor.
930. The supercapacitor of any one of embodiments 922 to 929,
wherein at least one of the electrodes is configured substantially
as one of an electric double layer capacitor or a pseudo capacitor
while not being configured substantially as the other of the double
layer capacitor or the pseudo capacitor.
931. The supercapacitor of any one of embodiments 922 to 930,
wherein upon application of a voltage across the electrodes, a
first sheet of charge of first polarity forms at surfaces of the
surface active material of the at least one of the electrodes
configured as an electric double layer capacitor, and a second
sheet of charge of second polarity forms adjacent to the at least
one of the electrodes configured as the double layer capacitor,
wherein the first and second sheets of charge are interposed by a
layer of electrolyte.
932. The supercapacitor of any one of embodiments 922 to 931,
wherein upon application of a voltage across the electrodes, the at
least one of the electrodes configured as a pseudo capacitor stores
energy by a reversible Faradaic redox reaction on the surface of
the surface active material.
933. The supercapacitor of any one of embodiments 922 to 932,
wherein the at least one of the electrodes comprising the at least
one of the zinc oxide and the manganese oxide are configured
substantially as a pseudo capacitor.
934. The supercapacitor of any one of embodiments 922 to 932,
wherein the at least one of the electrodes are configured
substantially as an electric double layer capacitor.
935. The supercapacitor of any one of embodiments 922 to 934,
wherein the electrolyte comprises an ionic liquid.
936. The supercapacitor of any one of embodiments 922 to 935,
wherein the ionic liquid comprises one or more cations selected
from the group consisting of butyltrimethylammonium,
1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium,
1-methyl-3-propylimidazolium, 1-hexyl-3-methylimidazolium, choline,
ethylammonium, tributylmethylphosphonium,
tributyl(tetradecyl)phosphonium, trihexyl(tetradecyl)phosphonium,
1-ethyl-2,3-methylimidazolium, 1-butyl-1-methylpiperidinium,
diethylmethylsulfonium, 1-methyl-3-propylimidazolium,
1-ethyl-3-methylimidazolium, 1-methyl-1-propylpiperidinium,
1-butyl-2-methylpyridinium, 1-butyl-4-methylpyridinium,
1-butyl-1-methylpyrrolidinium, diethylmethylsulfonium and
combinations thereof.
937. The supercapacitor of any one of embodiments 922 to 936,
wherein the ionic liquid comprises or more anions selected from the
group consisting of tris(pentafluoroethyl)trifluorophosphate,
trifluoromethanesulfonate, hexafluorophosphate, tetrafluoroborate,
ethyl sulfate, dimethyl phosphate, methansulfonate, triflate,
tricyanomethanide, dibutylphosphate,
bis(trifluoromethylsulfonyl)imide, bis-2,4,4-(trimethylpentyl)
phosphinate, iodide, chloride, bromide, nitrate and combinations
thereof.
938. The supercapacitor of embodiment 935, wherein the ionic liquid
comprises 1-ethyl-3-methylimidazolium tetrafluoroborate
(C.sub.2mimBF.sub.4).
939. The supercapacitor of any one of embodiments 922 to 938,
wherein the electrolyte further comprises a salt dissolved
therein.
940. The supercapacitor of embodiment 939, wherein the salt has at
least a cation that is different from a cation of the ionic
liquid.
941. The supercapacitor of embodiments 939 or 940, wherein the salt
comprises a cation selected from a group consisting of zinc,
sodium, potassium, magnesium, calcium, aluminum, lithium, barium
and combinations thereof.
942. The supercapacitor of any one of embodiments 939 to 941,
wherein the salt comprises at least an anion that is different from
an anion of the ionic liquid.
943. The supercapacitor of any one of embodiments 939 to 942,
wherein the salt comprises an anion selected from the group
consisting of chloride, bromide, fluoride,
bis(trifluoromethanesulfonyl)imide, sulfate, bisulfite, nitrate,
nitrite, carbonate, hydroxide, perchloride, bicarbonate,
tetrafluoroborate, methansulfonate, acetate, phosphate, citrate,
hexafluorophosphate and combinations thereof.
944. The supercapacitor of any one of embodiments 939 to 943,
wherein the salt comprises an organic salt.
945. The supercapacitor of any one of embodiments 939 to 944,
wherein the salt comprises an anion selected from the group
consisting of tetraethylammonium tetrafluoroborate,
tetraethylammonium difluoro(oxalate)borate, methylammonium
tetrafluoroborate, triethylmethylammonium tetrafluoroborate,
tetrafluoroboric acid dimethyldi ethylammonium,
triethylmethylammonium tetrafluoroborate, tetrapropylammonium
tetrafluoroborate, methyltributylammonium tetrafluoroborate,
tetrabutylammonium tetrafluoroborate, tetrahexylammonium
tetrafluoroborate, tetramethylammonium tetrafluoroborate,
tetraethyl phosphonium tetrafluoroborate, tetrapropylphosphonium
tetrafluoroborate, tetrabutylphosphonium, tetrafluoroborate and
combinations thereof.
946. The supercapacitor of any one of embodiments 939 to 943,
wherein the salt comprises an inorganic salt.
947. The supercapacitor of embodiment 946, wherein the inorganic
salt comprises a salt selected from the group consisting of LiCl;
Li.sub.2SO.sub.4, LiClO.sub.4, NaCl, Na.sub.2SO.sub.4, NaNO.sub.3,
KCl, K.sub.2SO.sub.4, KNO.sub.3, Ca(NO.sub.3).sub.2, MgSO.sub.4 and
combinations thereof.
948. The supercapacitor of any one of embodiments 922 to 947,
wherein the electrolyte comprises an acid selected from the group
consisting of H.sub.2SO.sub.4, HCl, HNO.sub.3, HClO.sub.4 and
combinations thereof.
949. The supercapacitor of any one of embodiments 922 to 947,
wherein the electrolyte comprises a base selected from the group
consisting of KOH, NaOH, LiOH, NH.sub.4OH and combinations
thereof.
950. The supercapacitor of any one of embodiments 939 to 941 and
943 to 949, wherein the salt comprises the same anion as an anion
of the ionic liquid.
951. The supercapacitor of embodiment 950, wherein the salt
comprises zinc tetrafluoroborate Zn(BF.sub.4).sub.2.
952. The supercapacitor of any one of embodiments 922 to 951,
further comprising a separator interposed between the pair of
electrodes.
953. The supercapacitor of embodiment 952, wherein the separator
comprises a plurality of frustules.
954. The supercapacitor of embodiment 953, wherein the separator
further comprises graphene oxide.
955. The supercapacitor of any one of embodiments 922 to 954,
wherein the frustules comprise chemically unmodified frustules.
956. A method of fabricating a supercapacitor, the method
comprising: forming a separator between a pair of electrodes,
wherein the separator comprises frustules, an electrolyte and a
thermally conductive additive, wherein the thermally conductive
additive is adapted to substantially absorb a near infrared (NIR)
radiation upon being applied to the separator, thereby causing
heating of the separator to accelerate drying.
957. The method of embodiment 956, wherein the thermally conductive
additive is substantially thermally conducting and substantially
electrically insulating.
958. The method of embodiments 956 or 957, wherein the thermally
conductive additive comprises graphene oxide (GO).
959. The method of embodiment 958, wherein the GO comprises a
network of contiguous sheets contacting each other.
960. The method of any one of embodiments 956 to 959, wherein the
forming the separator comprises forming a mixture comprising the
frustules, a gel and the electrolyte.
961. The method of embodiment 960, wherein the electrolyte
comprises one or more of a solvent, a salt and an ionic liquid.
962. The method of embodiments 960 or 961, wherein the gel
comprises a gelling polymer.
963. The method of embodiment 962, wherein the gelling polymer
includes one or more selected from the group consisting of
polyvinylidene fluoride, polyacrylic acid, polyethylene oxide,
polyvinyl alcohol and combinations thereof.
964. The method of embodiments 962 or 963, wherein the gel
comprises the gelling polymer and the electrolyte.
965. The method of any one of embodiments 960 to 964, wherein the
frustules form a network of pores, wherein forming the mixture
comprises substantially completely filling the network of pores
with the gel.
966. The method of any one of embodiments 960 to 964, wherein the
frustules form a network of pores, wherein forming the mixture
comprises partly filling the network of pores with the gel.
967. The method of embodiment 964, wherein forming the mixture
comprises filing the network unfilled with the gel with the
electrolyte.
968. The method of any one of embodiments 956-967, wherein forming
the separator comprises printing using an ink comprising the
frustules and the thermally conductive additive.
969. The method of any one of embodiments 956 to 968, wherein the
separator comprises an electrolyte comprising an ionic liquid.
970. The method of embodiment 969, wherein the ionic liquid
comprises one or more cations selected from the group consisting of
butyltrimethylammonium, 1-ethyl-3-methylimidazolium,
1-butyl-3-methylimidazolium, 1-methyl-3-propylimidazolium,
1-hexyl-3-methylimidazolium, choline, ethylammonium,
tributylmethylphosphonium, tributyl(tetradecyl)phosphonium,
trihexyl(tetradecyl)phosphonium, 1-ethyl-2,3-methylimidazolium,
1-butyl-1-methylpiperidinium, diethylmethylsulfonium,
1-methyl-3-propylimidazolium, 1-ethyl-3-methylimidazolium,
1-methyl-1-propylpiperidinium, 1-butyl-2-methylpyridinium,
1-butyl-4-methylpyridinium, 1-butyl-1-methylpyrrolidinium,
diethylmethylsulfonium and combinations thereof.
971. The method of embodiments 969 or 970, wherein the ionic liquid
comprises or more anions selected from the group consisting of
tris(pentafluoroethyl)trifluorophosphate,
trifluoromethanesulfonate, hexafluorophosphate, tetrafluoroborate,
ethyl sulfate, dimethyl phosphate, methansulfonate, triflate,
tricyanomethanide, dibutylphosphate,
bis(trifluoromethylsulfonyl)imide, bis-2,4,4-(trimethylpentyl)
phosphinate, iodide, chloride, bromide, nitrate and combinations
thereof.
972. The method of any one of embodiments 969 to 971, wherein the
ionic liquid comprises 1-ethyl-3-methylimidazolium
tetrafluoroborate (C.sub.2mimBF.sub.4).
973. The method of any one of embodiments 969 to 972, wherein the
electrolyte further comprises a salt dissolved therein.
974. The method of embodiment 973, wherein the salt comprises a
cation selected from a group consisting of zinc, sodium, potassium,
magnesium, calcium, aluminum, lithium, barium and combinations
thereof.
975. The method of embodiments 973 or 974, wherein the salt
comprises at least an anion that is different from an anion of the
ionic liquid.
976. The method of any one of embodiments 973 to 975, wherein the
salt comprises an anion selected from the group consisting of
chloride, bromide, fluoride, bis(trifluoromethanesulfonyl)imide,
sulfate, bisulfite, nitrate, nitrite, carbonate, hydroxide,
perchloride, bicarbonate, tetrafluoroborate, methansulfonate,
acetate, phosphate, citrate, hexafluorophosphate and combinations
thereof.
977. The method of any one of embodiments 973 to 976, wherein the
salt comprises an organic salt.
978. The method of any one of embodiments 973 to 977, wherein the
salt comprises an anion selected from the group consisting of
tetraethylammonium tetrafluoroborate, tetraethylammonium
difluoro(oxalate)borate, methylammonium tetrafluoroborate,
triethylmethylammonium tetrafluoroborate, tetrafluoroboric acid
dimethyldi ethylammonium, triethylmethylammonium tetrafluoroborate,
tetrapropylammonium tetrafluoroborate, methyltributylammonium
tetrafluoroborate, tetrabutylammonium tetrafluoroborate,
tetrahexylammonium tetrafluoroborate, tetramethylammonium
tetrafluoroborate, tetraethyl phosphonium tetrafluoroborate,
tetrapropylphosphonium tetrafluoroborate, tetrabutylphosphonium,
tetrafluoroborate and combinations thereof.
979. The method of any one of embodiments 973 to 978, wherein the
salt comprises an inorganic salt.
980. The method of embodiment 979, wherein the inorganic salt
comprises a salt selected from the group consisting of LiCl,
Li.sub.2SO.sub.4, LiClO.sub.4, NaCl, Na.sub.2SO.sub.4, NaNO.sub.3,
KCl, K.sub.2SO.sub.4, KNO.sub.3, Ca(NO.sub.3).sub.2, MgSO.sub.4 and
combinations thereof.
981. The method of any one of embodiments 969 to 980, wherein the
electrolyte comprises an acid selected from the group consisting of
H.sub.2SO.sub.4, HCl, HNO.sub.3, HClO.sub.4 and combinations
thereof.
982. The method of any one of embodiments 969 to 980, wherein the
electrolyte comprises a base selected from the group consisting of
KOH, NaOH, LiOH, NH.sub.4OH and combinations thereof.
983. The method of any one of embodiments 973 to 980, wherein the
salt comprises the same anion as an anion of the ionic liquid.
984. The method of any one of embodiments 973 to 980, wherein the
salt comprises zinc tetrafluoroborate Zn(BF.sub.4).sub.2.
985. The method of any one of embodiments 956 to 984, further
comprising drying the separator by subjecting the separator to the
NIR radiation.
986. The method of embodiment 985, wherein drying the separator is
performed for a duration not exceeding 1 minute. The method of any
one of embodiments 956 to 985, wherein the supercapacitor is
according to any one of embodiments 803 to 847.
987. The method of any one of embodiments 956 to 985, wherein the
supercacitor is according to any one of embodiments 848 to 883.
988. The method of any one of embodiments 956 to 985, wherein the
supercacitor is according to any one of embodiments 884 to 955.
989. The method of any one of embodiments 956 to 985, wherein one
or more components of the supercapacitor are manufactured according
to the method of manufacturing the printed energy storage device
according to any one of embodiments 98 to 115.
990. The method of any one of embodiments 956 to 985, wherein one
or more components of the supercapacitor are printed using the ink
according to any one of embodiments 116 to 154.
991. The method of any one of embodiments 956 to 985, wherein the
frustules are extracted according to any one of embodiments 160 to
321.
992. The method of any one of embodiments 956 to 985, wherein one
or more components of the supercapacitor are printed using the ink
according to any one of embodiments 520 to 524.
993. The method of any one of embodiments 956 to 985, wherein at
least some of the frustules comprise a surface active material
comprising manganese-containing nanostructures formed according to
any one of embodiments 525 to 546.
994. The method of any one of embodiments 956 to 985, wherein at
least some of the frustules comprise a surface active material
comprising zinc-oxide nanostructures formed according to any one of
embodiments 620 to 644.
995. The method of any one of embodiments 956 to 985, wherein at
least some of the frustules comprise a surface active material
comprising the oxide of manganese formed according to any one of
embodiments 645 to 655.
996. The method of any one of embodiments 956 to 985, wherein one
or more components of the supercapacitor are printed using the ink
according to any one of embodiments 656 to 683.
997. The method of any one of embodiments 956 to 985, wherein one
or more components of the supercapacitor are printed using the ink
prepared according to any one of embodiments 684 to 705.
998. The method of any one of embodiments 956 to 985, wherein one
or more components of the supercapacitor are formed according to
any one of embodiments 706 to 739.
While the methods and devices described herein may be susceptible
to various modifications and alternative forms, specific examples
thereof have been shown in the drawings and are herein described in
detail. It should be understood, however, that the invention is not
to be limited to the particular forms or methods disclosed, but, to
the contrary, the invention is to cover all modifications,
equivalents, and alternatives falling within the spirit and scope
of the various implementations described and the appended claims.
It is also contemplated that various combinations or
sub-combinations of the specific features and aspects of the
embodiments may be made and still fall within the scope of the
invention. It should be understood that various features and
aspects of the disclosed embodiments can be combined with, or
substituted for, one another in order to form varying modes of the
embodiments of the disclosed invention. Further, the disclosure
herein of any particular feature, aspect, method, property,
characteristic, quality, attribute, element, or the like in
connection with an implementation or embodiment can be used in all
other implementations or embodiments set forth herein.
Any methods disclosed herein need not be performed in the order
recited. The methods disclosed herein may include certain actions
taken by a practitioner; however, the methods can also include any
third-party instruction of those actions, either expressly or by
implication. For example, actions such as "adding the frustules to
an oxygenated manganese acetate solution" include "instructing the
adding of the frustules to an oxygenated manganese acetate
solution."
The ranges disclosed herein also encompass any and all overlap,
sub-ranges, and combinations thereof. Language such as "up to," "at
least," "greater than," "less than," "between," and the like
includes the number recited. Numbers preceded by a term such as
"about" or "approximately" include the recited numbers and should
be interpreted based on the circumstances (e.g., as accurate as
reasonably possible under the circumstances, for example .+-.5%,
.+-.10%, .+-.15%, etc.). For example, "about 3.5 mm" includes "3.5
mm." Phrases preceded by a term such as "substantially" include the
recited phrase and should be interpreted based on the circumstances
(e.g., as much as reasonably possible under the circumstances). For
example, "substantially constant" includes "constant."
The headings provided herein, if any, are for convenience only and
do not necessarily affect the scope or meaning of the devices and
methods disclosed herein.
* * * * *
References